1) Over stalking. Save yourself some time, anxiety and preconceptions. You don't have to know what their ex looks like nor do you need to see a million pictures of them with other people that make you ask yourself a million questions. Get to know the person on your dates, not on your computer. That's what dates are for after all...
2) Comparing to exes. OMG so they said this one sentence that your ex used to say all the time. No, it does not mean you have to stay clear from them. Everyone deserves a clean slate and you probably need it more than most...
3) Not offering to pay. I know this can get awkward but we should all, ladies and gents, be offering to pay the bill and if not at the first date, then try at the second.
4) Not having a good sense of humour. Take that stick out of your a** and have a good time for once in your life.