How can i stop with my mean habits?

To be honest, you are most likely NOT UGLY. I am not saying this because I have seen you. But most people in the world are not ugly - just average-looking or a little less than average-looking. Just because you think someone is ugly, does not mean you should make fun of them for it. Most people who are considered ugly are going to made fun of it for a long time. I applaud you for trying to change though, that shows some maturity.