I came out a couple of months after I put all the pieces together and realized I was gay. Unfortunately for me, I was 32, had been married for eleven years and had two kids. Of all the things I can recommend not doing, that is by far and away the biggest, though I wouldn't trade my kids for anything. You've no idea how much I'd have liked to have done it earlier.
That all comes in time. It's a matter of getting out, meeting people, and learning how to deal with them. If you're lucky it comes easily. If you're not, it's going to suck.
But... don't worry about it.
When you get right down to it, the only person who has to look at you every day, the one you can't get away from, is you. Be someone worth being, someone you can be proud of, someone you're not ashamed to look at in the mirror in the morning.
Eat right, exercise, and get in shape if you're not there now. You'll feel better and, if a situation goes to hell, it's a damn sight easier to run away if there's not all that much of you to move.
Learn to fight. Aikido or judo if you don't really want to hurt someone, kung fu or tae kwon do if you do. You'll probably never have to use it, but knowing you can will give you the confidence to deal with things if you have to. You'll also find that the confidence that comes with knowing you can kick someone's ass means you'll be in situations where it may happen less often.
Learn another language, learn to play an instrument, learn how to cook, and learn how to do them well. Hell, when you do anything do it the best you can, even if that's not very good, and try to do better next time. Find something you like (not something you're good at, mind, something you like) and do it. Throw your heart and soul into it.
If you can be out without much crap, do it. Hiding hurts. If you'll get too much crap, then wait, since there's a lot more to you than just being gay. It's an important part, and shouldn't be denied, but there's no reason to dive into hell for it. If you must, wait. You know your parents better than we do, though not as well as you think you do, so if you don't feel you can come out to them, don't. If you can, do it.
If you're comfortable with who you are and good at what you do, the relationships will follow, and they'll be with people worth being with.