I've been keeping an engineer's notebook for the last couple of years, and I feel like it has really helped me to be on time to meetings and not forget important tasks. It has also helped me grow as a software engineer. I'm learning more from my tasks and pushing my work further.
It's kind of dorky and, especially at first, I felt really self concious carrying around my notebook AND my laptop. Now, I still feel kind of self concious, but I've decided I don't care if people think I'm a dork (I really am, ask my family). Besides, I've started noticing others carrying around notebooks, as well.
I'm not sure that this has a whole lot to do with what I'm doing, and you can use whatever you like, of course. I think it does make sense to use something that's not hard to look at, as well as something that feels nice to write on. Also, I think it kind of needs to have a cover, especially if you plan on keeping them around for reference or if you plan to write things in there that should be kept confidential, so that rules out the free legal pads in the supply room.
I've been using Moleskine cahier journals, 7.5 x 9.75 inches. I really like the fancier ones with leathery covers and built in bookmarks, but I don't want to hold back from using it (because I spent a lot of money on it). However, I do want it to be high quality, something that feels comfortable to carry around, something that's easy to read and write in.
I also tend to slap some stickers on the front of it. It lets me be a little more discerning about what stickers I put on my laptop. If I don't like the sticker after I put it on my notebook, I'll be on to a new notebook in a few months, so it's no big deal.
I know a lot of people that like to use fancy pens, like fountain pens or space pens, but I just use the boring ones from the supply room at work. They work well and reliably, last a long time, and I have a huge supply. I also leave it inside my notebook, using it as a sort of bookmark. It makes it a little out of shape, but not enough that it looks terrible.
I pulled elements from a lot of places for the layout, and have adjusted it quite a bit while I've been using my notebooks. This part feels almost more personal than your choice of notebook and pen. Tweak it to something you like, something that works good for you. Bullet Journal is the most prominent source of inspiration for my layouts, but I've customized them pretty heavily.
First of all, I write my email and phone number on the front of every notebook. I haven't misplaced one, yet, but when I do, I hope it will find it's way back to me. I also write the start date (and the end date when I move on to the next notebook) on the front cover.
I start each notebook with an index and a future log. I also number the notebooks, to make it easier to write references to older notebooks from future notebooks.
In the index, I try to add entries to the index, as soon as I title a new page. There's probably a good mix of specificity and generality in adding topics to the index, but I haven't figured it out, yet. Honestly, it probably doesn't matter as much as it feels like it does. I do know that it's usually a bit harder to find a note that I know I wrote, if it's in a past notebook, than I think it should be, but I still usually find them.
The Future Log
The future log is setup to give me 6 months of space in 2 facing pages. Then I just write the day and subject under the given month, along with a time, if I know it. If something comes up farther than 6 months out, I write it near the bottom with the full date.
The Rest of the Notebook
The rest of the notebook is a mix of the following types of pages. The monthly log and weekly log are always 2 facing pages. Otherwise, I usually go with a page per subject, whether it's a meeting, a lecture, a tech talk, or whatever.
I fill these pages out as I need to. I never create a meeting page until I'm sitting in the meeting. I don't create my weekly log until Monday morning (I find it's a good way to get rolling on the week).
The monthly log is basically a page of days in the month. I write the irregular events and meetings on this page, as well as use letters before the day to indicate some regular things, like on-call weeks or black days (no code ships to prod). I also add letters indicating the weekday next to each date.
There's usually some extra space at the bottom of the page, where I'll make some notes about things early next month or things I don't have room for on a single line for the day, above.
I use the facing page to write down significant things I did last month, goals I hit, operational oddities, big accomplishments, etc. These are the pages I tend to look back at when building my promotional docs or updating my resume. I've been pretty bad about updating these in a timely manner. Even when I don't get to it until the next month, I still find it helpful to review and write this stuff down.
The weekly log is where I write down my day to day stuff, tasks I intend to complete each day, meetings and events coming up each day, and random notes. This tends to be where I spend most of my time. As I go through my email, I tend to write things that take longer than a minute or two, down here, to take care of after getting through my email. Also, as I get instant messages from people, asking for something or for help, or whatever... if it takes longer than a couple of minutes, I write it, here, and take care of it between tasks. This allows me to be responsive, get the random requests completed, and still get my actual work (development of new features or bug fixes that have already been found and priotized) done.
The weekly log is two facing pages. The first page is split into 3 sections, a task section, calendar section, and a notes section, from top to bottom. On the facing page, I write my daily logs for the current week.
The tasks section is where I write tasks that come up during the week, which I may have time to take care of later in the week... but not today. This includes things like action items from the operations meeting, or something I noticed while working on another task... A lot of these items are "Create a story in SIM (internal JIRA like tool) for thing I noticed."
The calendar section is basically a copy of the monthly log, but only for the upcoming week. I also stopped including the starting Monday, since that get's written down in the daily log, with any events that are happening... This removes the need to refer back to the monthly log, throughout the week.
The notes section is just for jotting down random notes throughout the week. Some weeks it stays empty, however, there's usually something there. Ocasionally, I write random quotes that I feel are insightful, here. I also write things I need to remember for a few minutes to transfer to another app, like ticket numbers or aliases. I'll also sometimes write notes for meetings that I don't feel I'm going to need a lot of notes for, where I'm not really interested in the main topic, but there more as a SME to lend guidance or because my manager thought I should attend.
The daily log is where I write the meetings scheduled for the day, as well as tasks I intend to work on. These I write, as I need them. Basically, at the start of the day, I'll skip a line from where I left off yesterday, and write today's date, then start copying meetings from my calendar and copy tasks from my task list on the previous page or the sprint board (or even things I need to do for upcoming meetings). I continue to add things, here, throughout the day, as they come up, including noteable things that happened (one or 2 lines only).
When writing a meeting or appointment, I use a circle for the bullet (this is kind of bullet journal-ish), then write the meeting time, followed by a short description / title. I then write the conference call code and the conference room number.
I use a dot for the bullet with tasks, then I cross out the dot when I finish the task. If I don't finish it and it moves to the next week, I'll throw an angle bracket pointing forward to indicate that I moved it forward. If I move it to a sprint task or back to my weekly task list, I put an angle bracket pointing backward on it. I'll usually write a story identifier, a page number, or something that I can refer to, to get more information about the task (this is mostly for later, when I'm reviewing or looking for information).
Finally, dashes are my bullet of choice for information or notes. These will also have references to pages, or tickets, or the sprint task, or whatever, for future me.
Anything that is important or urgent, gets a star to the left of it, so I keep looking at it, every time I look at my notebook.
Subject pages are for meetings, lectures (tech talks), interviews, notes about bugs / fixes, software designs (data structures, flows, API, etc), and pretty much anything else you might want to take notes for. I tend to give each of these a single page. When I'm sure something won't take a full page, I'll add it to a page that doesn't have a lot of content. If something ends up not fitting on a single page, I'll continue it on the next empty page (usually the next page), but I really do try to fit it on a single page. When I'm making notes about something I want to keep extra private, I usually flip back a few pages and add it to a page that doesn't have a lot of content. I still add it to the index, so I can find it later. This just keeps it private if someone happens to look at my notes during a meeting or something.
I tend to focus on writing down dates, timelines, concerns, and promises, when I'm in meetings. I've referred back to my meeting notes many times to clarify what another team said, versus what they did. It's not always the clarion that I've hoped it would be, but it's usually helpful.
When it comes to tech talks and other lectures, I like to write what's not on the slides... I can always request a copy of the powerpoint or view the slides in the video on silent, later. The best tea is usually the part that's not written down.
I really like to take hand written notes. It let's me focus more on what I'm doing, and less on getting the text and everything into the perfect format. I can always focus on format after the fact. It also kind of helps that I don't write as fast as I type, it forces me to paraphrase, which I find helps me to retain the information.
The more personal meetings, like 1 on 1's or interviews that I'm on the receiving end, tend to require a bit of tact. I'll write some things down before the meeting, maybe some things I want to bring up, or some thoughts about things I expect others will bring up. Then, after the meeting, I'll write down more notes about what actually came up, how were my questions answered, what are my thoughts, now? It's good to review these things soon after the meeting, anyway.
The reflections are when I just write. I write about what I'm feeling and thinking. I write about what's happened recently. I don't tend to write these, often, sometimes I don't even have one in a whole notebook. When I do write them, I tend to go on for 2 or 3 pages, though, so I never start it on an orphaned page. I really think it's helpful, and I (not so much enjoy, more like) find it enlightening when I go back and read them.
Lastly, I wanted to talk a little about style. I've been working on my handwriting since I started using notebooks a few years ago. It's still atrocious, but I usually don't have to try too hard to understand what I wrote, anymore. I think it's helped others understand when I write things on whiteboards, as well... which is also good for my career.
I like to bold things to add emphasis (just go over the letters a few times with the pen). I sometimes bold headings, though usually I don't have time to while writing it. Usually I'll make the headings in caps and bold words and phrases.
A lot of times, sections will just be split by white space, but if things are getting crowded or hard to tell where one secion ends and another begins, I'll draw some lines in there. I also draw large punctuation next to separate thought and question blocks.
When I'm particularly bored in a meeting that it would be awkward to just leave, I'll sometimes just draw on the meeting page... As a bonus, it looks like I'm taking notes, but, if it's not awkward to leave, I just go...
Carry your current notebook everywhere with you at work, whether you have your laptop, or not. Also, it's a good idea to keep your last notebook in your backpack, so you can reference it, if necessary.
Make a point to open your notebook and title the page when you get to a meeting or event. Before you konw it, you'll be the developer that takes notes, then you'll notice more people writing things down (it tends to spread).
Eventually, you'll have a pile of notebooks that you can rifle through. You'll have lists of accomplishments to add to your resume and promotion documents. You may even end up with a tool to measure your performance over the years.