Get a little booklet and write down a one page (short and pointy) report one each race day. About what your tune and trim settings were. What worked and what didn't work. What felt good and what felt bad.
Very good point that I had forgotten about. I do this as a matter of course when I'm setting up a new boat and until I know what settings I need I take my "little black book" with me everywhere. I had forgotten about this as every time I get back from sailing I download the GPS plots for the day and make my notes on my PC. It's part of my "putting my sailing kit away" routine and I had forgotten I even do it.
Another one is talk to your crew (or your self if sailing single handed) as with a crew around they know what you are planning (and can change your mind if it is dumb) and I find that if I talk a plan out to my self, I usually spot any holes in it before I am in them - You can get some funny looks if people are close to you mind
