I have tried to keep a journal several times in my career, but after a couple of weeks I usually get too lazy to keep it up. Does not seem to affect my performance one way or another. After doing this for long enough I know when I am making a mistake and I correct it immediately.
Info about trade (time, sector, type of setups, long, short, etc.) Mood im in... entry times.. stop price and why... exit times....and reason... outcome and expectations... that kinda sums it up...