tips on clothes shoping from a noob to another:
buy simple buy safe, usually a simple solid colour looks better than a big textures, also they are easier for noobies like us to understand, blue looks good with black and grey looks good with white and so on.
never buy without checking other shops first (some have the same thing but at lower prices ;D).
most important of all make sure the clothes you pick fit you, this is what makes most people look bad in clothes they buy, it's either too big or too small, a good way to check is if the arm seams go from your arm pit to the tip of the shoulder

also try out some clothing blogs they usually give great tips on how to dress nice and cheap
hope it helps and good luck shoping ;D