This video explains what not to do on a first date. This video is for lesbian but could be sound advice for straight people too.
1) Do not get into a debut about politics.
2) Do not talk about religion.
3) Do not talk about money or how much money you make.
4) Do not talk about former relationships.
5) Do not talk about dating around or your other dates, when you are on your current date.
6) Do not talk about past childhood traumas or bad things that have happened to you.
Let people get to know you first and slowly leak information. Treat a first date like a job interview.