the point about talking to strangers is a good one, because youll learn that actually people arent going to turn around and bite your head off if you try to smalltalk with them - this confidence in speaking to strangers can then extend to starting up conversations with girls with the aim of getting a date.
also another good tip for dressing, when you look at fashion magazines or whatever, try to pick out a certain look that you like. find an actor that you would like to look like, and buy clothes that they would wear. so e.g you want to be a brad pitt sort of man, then build wardrobes around nice jeans, nice t shirts and maybe a blazer for neater occassions; if you want to be a george clooney, focus on proper trousers, proper shoes, suits, buttonup shirts etc
also one more thing, make sure you have nice shoes. it doesnt matter if they are trainers or proper dress shoes, make sure they arent falling apart. apparently its a major thing girls notice - if you arent taking care of your feet then youre probably not taking care of other parts of yourself and therefore couldnt take care of them.