Myself, I have two trains of thought on this:
1)Continue to live your life as you normally would, and just exert some degree of discipline. Hey, if you are young you should be able to have fun right? And you don't have to drink in order to do that. A wise man with 25 years of sobriety once told me something that made a lot of sense: He said staying sober shouldn't take your life away from you, it should give it back! And it's so true! But that being said, if you are in fact going to go out to a party, wedding, bar, etc. be prepared to have someone's number handy, and get out of there the SECOND you start feeling tight. Because at the end of the day people, let's face it: You're going to have to exert some degree of discipline in your sobriety. You simply can't live under a rock. I know this, because I've tried it many times, and always ended up getting drunk or high. It simply does not work. You CANNOT hide from booze and drugs the rest of your life. It just doesn't work.
and
2)Don't put yourself into precarious situations more often than necessary. Yes, go out, have fun. But at the same time, don't go to a bar five nights a week and expect not to drink. Don't hang out around drug houses five days a week, and expect not to use. In other words: Don't push your luck. Make calculated decisions. Like the slogan goes (and I know it sounds hokey) "Think,think,think!" Weigh the pros and cons of the situations! I go out to bars on occasion. Sure! I go to watch UFC pay-per-views at my local Boston Pizza, and there's people drinking there. I just drink water. And I start to feel tight, I get up and leave. It really is that simple. (Hasn't happened yet though.) It's all about your frame of mind. If you're tight beforehand you probably shouldn't push your luck.
Bottom line: Nobody expects a young person in sobriety to not go out. Go out. You can't avoid booze (and to a certain extent drugs) in real life. If you wanna' live under a rock by all means, do so. But I'm telling your right now, that you will not be a happy camper. And I speak from experience. Why shouldn't I be able to go to hockey game, a concert, a wedding or whatever? Just because you no longer drink or do drugs, doesn't mean you are somehow inhumane. Do all the things you would normally do, just don't push your luck. It really is that simple.