Teaching Technique #3: Keep a Journal
I found this to be a very helpful tool. It works excellently when you are just starting to teach a class. I do not know if you would need to keep one once you already taught the class for several years.
Each day after class (well, I usually remembered), I wrote a brief journal entry on what we did, what worked, where the students had trouble, what seemed to bore them beyond belief, when class was too short, when I ran out of time, etc. The first time around it was useful as a reflection tool, as well as for some slight venting of frustrations. It also helped me feel less guilty when I "failed" because I recorded it so I could improve the next time around.
Then when I went to teach the class the second year, I used the journal to help me reorder the class topics in my syllabus, and to figure out which ones needed more time and which ones needed less. In addition, during the second year of teaching, I often consulted the journal to see what I had done while teaching a particular topic so I could make changes as necessary. I continued the journal for the second year and have since looked back on it for various information - e.g. what questions I asked during pop quizzes, what ice breaker I used.
Keeping a journal may not work for everyone, but I found it very helpful.