The Mortal side
There comes a time in a half-blood's life when he or she begins to wonder about the opposite gender.
Let start how to get a girlfriend since I know how. For the guys, first you have to catch her eye. Then you have to start flirting them. After that measure how much she likes you and ask her out. Once you have a girlfriend take her out on a date (Well that's obvious), make sure to take her where she wants to go. After that hang 10 and enjoy the relationship.
As for girls, sometimes, it doesn't matter how pretty you are or how rich you are, your boyfriend just has to look on the inside. If you want to look like that, fine, just know some boys don't like that. When you're flirting with a boy, just act natural, don't let the butterflies get to you. Get to know each other and find common interests. Once, you get asked out on a date, make sure you and your boyfriend agree on a place to go. I personally have no experience with dating, but when you're on a date, don't go overboard with makeup and your outfit but more on revealing your inside. Once again, act natural and find a good topic to speak about. If you think you're in a private enough location, talk about demigod related things. After that, enjoy your relationship while it lasts.
Okay how about be your self and try too get his attention and if it involves make up and shoes (*Barf*) only consider that and try to show him what he means to you and maybe spend some time together. Personally I wear make up because I feel I'm ugly but you all shouldn't. It covers your beauty and also hurts your skin. But, watch out you're girl or boyfriend could end up evil...(-Lane the one in bold)
The Demigod side
You should find out if the person you like is a demigod or a clear-sighted mortal. Whether ur a guy or a girl you DON'T want be in a relationship with a girl/guy if they aren't a demigod or a clear-sighted mortal because you will attract monsters and the relationship will suffer. If you can help it don't tell ur a demigod unless a monster attacks and you have to tell the truth. But do not withold the truth unnecessarily.
If you break up
From my experience I know that a break-up is hard especially with the war going on. Kate cheated on me with the guy that killed my sister. The emotional pain you will feel if this happens to you is like being stabbed with rusty dagger (that's happened me before and technically, it hurts more, but moving on). Here's how you deal with it: relax take a deep breath, wait a few days. If you dumped him or her try to show forgiveness. I he or she dumped you show complete remorse and they might get back together with you. If he or she doesn't get back together with you, just find another girl or guy.