I seem to be having a hard time thinking before I speak. This is not good. At least not for me. I say things that are sarcastic or unkind without thinking. Then I am always sorry. I think it is good to think about what I say first instead of afterwards.
If you have this problem, maybe these three tips will help you.
Listen to the other person and then form your answer.
Ask yourself if you would like this to be seen in writing.