[Mike]

I have a pretty solid theory that girls like to date guys that offer some of the same kind of protection that they felt from their fathers. You should be kind of like a father figure that is younger and not illegal to have sex with.

I don't have very much experience since I've only had 2 relationships that lasted for more than a year, but in the previous one and my current one (which is still going strong) I have made a special effort to make sure that the girl felt totally safe and taken care of when she's with me. If you never flake out and never appear weak or incapable, she will see you as reliable and masculine and it will trigger her instinct that tells her she's found a viable mate. Obviously most guys are gonna fuck this up sometimes but if you come close to this you can stand out from the other males in your competition area.

In terms of opposites and similarities it's pretty simple as far as I can tell. Your personalities should be similar enough that you get along well but it helps if there are little quirks about each of your personality that are different but not annoyingly so. Like stuff you can make fun of and love at the same time. Interests kind of work the same way.