Good habits get built slowly, strand by strand and thread by thread, into mightly cables. Good habits will lead you to ever greater success.
A good habit for self improvement is to journal at the end of each day. The way to make it an even better write-up, and for it to help you improve further faster, is to include:
1. Goals for that day (which you can write up as the day begins or the night before)
2. A summary of the day past (just like in a normal journal)
3. What went right — at least one thing that went as expected or better than expected
4. What went wrong — at least one thing that went worse than expected
5. What was the root cause of the most prominent Best and Worst of the day
That looks like more work. It’s really not much more, and is significantly more helpful.