Don't talk about your ex. Big no. Even if you still have issues/feelings for your previous one, you don't want to scare away a potential relationship, unless you want to friend zone him ASAP.
Be seductive but don't be sexually aggresive with what you wear. Will give a wrong impression.
Don't be too difficult to unlock. Don't make the other one beg for longer answers. You'll pass as apathetic and boring to be with.
Don't let out big traumas of your past till there is enough confidence/trust. People might think you're broken, trying to find somone to help them.
Don't lie. If the date goes well and you see each other many times after that, people will find out you lied in the first date and they won't forget about that. (about your income, your environment, having or not having things, having a kid -!-)
You should end the date stating how you want to be considered as. If you know you it didn't went well/you're not interested, then maybe suggest going home separate ways, definitely paying separately. Just a quick hug. If you want the romance to bloom, suggest seeing each oher some other time and probably throwing out what days of the week you're available. Give them your number or email or more ways to find you. Let them take you home, probably let them pay, taking this as a hint for "it will be on me the next time".
Fart, burp, scratch certain body parts, swear too much, talk about ex girlfriends, talk about how unfortunate you are if you feel that way, be pessimistic, talk about how you'll never find a significant other, ditch your date, get drunk, get aggressive, start talking about a wedding and how many kids you want, forget to mention quite important stuff about yourself, not asking anything about your date, take phone calls (I really hate it when someone does this!), ...
I try to always keep the conversation as light-hearted and upbeat as possible. If the conversation is too heavy or too personal, for me it sends the wrong signals.
The last date I went on, the guy told me an "embarrassing" story about his poop giving way too much descriptive information... needless to say.. that conversation would fall under the "too personal" list of things to share :)
I can't believe you'd wanna memorize a list, only to have to focus on what "not" to do. That seems like it would really take away from the moment, but if it works for you, there are a lot of good answers here. Simply put you should be yourself. If you wanna look like a low-life jerk who has no care or respect for others, go out of your way to fart in public or maybe wipe some boogers on her sleeve. But if you wanna come off with class and intellect then use your head man. It really can't be that hard to understand how you want to live your life.
"Don't tell personal stuff or how you actually feel" and "don't play tricks by being mysterious", wow, I guess the date were we sit awkwardly opposed of each other silently waiting until it was over was actually perfectly played then...
Don't talk too much about yourself. Don't give completely straight answers, tease a bit. The more you joke around and don't take things too seriously, the more likely a girl is to fall for you. Serious guys that treat things like a job interview never get second dates.
For guys: Don't talk too much, let her talk about herself and pretend to listen and care. Then if she asks you any questions about yourself just give vague answers as to not give away your mysterious aura.
Sources: Bitches love mysterious men and talking about themselves.