I do write quite a bit, including in the iOS app I have been working on (hint hint). If I ever muster up the courage to look back on what I've written in the past, it's pretty obvious to see how I've changed. In the present, I try to recognize the times I've handled a situation better than I would have in the past (sometimes I don't). I think the hard part is that personal growth often isn't linear and it's difficult to measure.
Yes, doing it already, as it is especially true if you're improving yourself—I am documenting everything! Whether it's a goal I want to achieve or a skill I want to improve upon, it's not enough to just set a goal and hope that you'll get there at some time.
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