Gay Bar etiquette can seem difficult but it shouldn't worry you if you are 23. The secret is to relax. I would suggest going to a bar early before it gets too busy, chat to the bar staff, buy a drink, read a magazine, watch and wait. Smile and someone should hit on you. If you are not interested in them, then don't be rude but make it clear and don't waste their time. If you are interested in them explain that you are new to the scene and what you are looking for. If you see someone who interests you then approach them, the obvious lines usually work to get you in - is anyone sitting here? can i buy you a drink?