How to keep track of what you learnt?

This is a nice article that resonated with the method that I use to learn. I use the notepad approach, I keep a diary/notepad and write what I learn and it serves dual purposes, as an index for my learnings (so that I can go back and quickly reference) and the act of writing it makes me retain it longer.

http://www.freestylemind.com/how-to-keep-track-of-what-youve-learnt/