My advice?
Don't think you have to wear a uniform to be a part of it, you don't. Just dress like any other 20 year old.
Vinyl wise, the scene is built on original records and there are plenty of cheaper end ones to get your teeth into for a start, plus some good reissue labels like kent. Don't buy any of those shite modern bootlegs that are all over ebay.
Find a local venue that suits you and get out and enjoy yourself, thats what its all about - don't take it too seriously BUT take time to learn the way of things.
All the best with it