1. Date a boy who makes you happy, but marry him only if he makes you laugh deep-belly rumbles that hurt your ribs as the expand outwards> Date him when he sees that you're hurting and he gives you a moment to feel that pain like a handprint spreading across your consciousness, marry him only if he can make you smile even while you're ugly crying. The world is not a kind place. You will feel a lot of pain. Make sure you are with someone who makes it all bearable. Humor is and excellent gauge of intelligence. Life gets boring. Find someone who makes the banal interesting.
2. Make sure he has scars on the back of his hands, it's a good sign he has experience either fighting or making things -- creation is an act of selflessness and bruised knuckles are a good sign he knows how to defend himself. You've got too much soul to be handled by someone who has never been passionate. If he's never thrown a punch, let him at least have tasted the insanity of bringing an idea int existence. Rough palms are better than soft ones, they have been salted by this earth and made into leather. Callouses are evidence he has lived, that he has broken his skin and been in pin over and over and over again and still came back to the source of it.
3.Before you say yes, get him angry. See him scared, see him wanting, see him sick. Stress changes a person.Find out if he drinks and if he does, get him drunk -- you'll learn more about his sober thoughts. Discover his addictions. See if he puts you in front of them. You can't change people baby girl. If they are made one way, it doesn't just wear off. If you hate how he acts when he's out of it now, you're going to hate it much worse eight years down the road. You might love him to bits but it doesn't change that some people just don't fit.
4.Trust your instincts. If he ever makes you feel unsafe, don't make excuses, just get up and leave. That's all there is to it. It's better to be safe than sorry.