1. Do not remember electronic wallet password
2. Do not back up your wallet
3. Do not research new services
4. Buy and sell based on feelings
5. Leave your money in the electronic money floor
I think it is common to the user and to the person who has experience on it because we are not too young if we understand bitcoin so it is common sense that we forget to do that. You can realize your post when you experience a lot on this forum and you can ask yourself on why you do that.