Assumptions-- assuming that the girl will go wherever you suggest, assuming that if you like something then your date will also love it, assuming that if you make a decision then it's decided whether she has an opinion on it or not, assuming that she won't mind if the date includes your buddies, assuming she'll love a particular movie because your ex adored it, assuming she won't mind you turning up at her home unannounced after you've had a night out with your mates, assuming that it's perfectly ok for you to go to the game every week without her even though it's her one day off work a week, and so on! Never assume anything, least of all your girl staying around if you continually assume she's happy with everything you do and say!

Comparison-- comparing a date with either one of your ex girl friends, or your mother! Ex girl friends should be a given and no you shouldn't even voice those comparisons aloud to anyone even your best bud because you never know if it'll get back to her and she's not going to be happy when it does! It could be that you think it's a complement to compare your date to your mother because you think your mom is super cool and a wonderful person. Your date on the other hand probably doesn't know this about your mom, and so to her you are saying she's old! Girls are pretty touchy on the subject of age so avoid this landmine!

Underestimating: girls are resourceful. VERY resourceful! They have an information network that the CIA would envy. You don't know what they know or how they know it, so if you're hiding something get it out in the open because you can be very sure that if it's out there, they're going to find it! They may not go looking for it, but because of their social networks, information will come into their hands 2nd hand, 3rd hand and beyond, but come it will, and so it's far better than it comes from you! If you're married, if you were ditched by your ex, if you've got children somewhere, if you've been "inside", once you get into a slightly steady relationship, you need to give her the information before someone else does. You may not get a good reaction, but it's going to be better than if she learns it from someone else.

Not all girls are alike and so treat each one that you date as a new experience without any of the baggage from other relationships. Don't have expectations of this date because of what your last date did. Don't think that because your last date yelled at you for opening a door for her that this date doesn't appreciate your thoughtfulness. Above all, be sincere because probably the most common mistake that guys make when dating girls is in not playing things straight. Make sure that you're honest about who you are, and where you are in life. Your date may not like what she hears, but at least she knows where she stands.