If you're following agile practices, you're conducting retrospectives...at the end of each iteration, the end of each release etc. You are inspecting and adapting your practices as you move through the project.
But how often do you do a personal retrospective? Are you reviewing your performance to see how you can do better in your role, whether you're the project manager, product owner, or a team member?
My company does quarterly reviews to see how we are tracking against the goals we set out at the start of the year, but even that isn't often enough. It's hard to remember what I did 3 months ago.
My solution is to sit down once a week or so and take time to journal. I use this as a way to reflect over what I've been working on and identify things that I could be doing better. It's an effective technique; I set some goals in writing and then review those goals on a regular basis. I can see if I am making progress or if I need to set a new direction. I've been doing this for a few years now, so I can look back at old journals to see if I'm facing the same challenges I've had in the past.
Give it a try. The only things you need are a notebook and a pen. I like to get away from my computer when I do this, but you may choose to use your computer instead. Make sure you can avoid distractions...turn off the phone and the IM. Take a few minutes to relax and take some deep breaths and then write whatever comes to mind. Sometimes my thoughts seem random but they usually lead somewhere.