Going to university next year, hopefully should i ........?

Going the LGBT societies sounds like a great idea. You don't actually need to declare your sexuality to join, though -- sometimes there are straight "allies" who attend the meetings. I don't think anyone should directly lie about their sexuality, but it is absolutely your choice if you don't want to come out first thing. Being around other LGBT people will probably give you more courage, though and if you do want a girlfriend, being out is very important. It's easier to find people that way, but also being "in the closet" (I hate that analogy too, grr) may rule out or discourage relationships with some women -- they won't want to be excessively secretive if they're already out, or may think the fact that you haven't declared yourself only means that you're bicurious. Those are the major pros and cons, I think, but ultimately it's up to you.

You can come out whenever you want. It's okay to not be out even in your late teens. Chances are, you aren't going to marry anyone you date in college, so it's not like "not being out," is going to affect your love life in the long run. However, once you really want a partner after college, you should really be out or come out immediately.

Do only what you are comfortable with

And yea, find an LGBT club on campus.

You should definitely be out. They will be much more understanding and it will be nice to start fresh and be yourself!