Best exercises for a Six Pack?

Im 15 years old am pretty thin. I want to have a six pack by summer but I don’t know what exercises will give me the best results. Ive been playing soccer for a while so my abs are strong, but you cant see the individual packs, even when im flexing. Im not asking for amazing six pack abs. I just want to know which exercises I should do so that after a few weeks you can start to see a result of individual packs and eventually a very good set of abs. How many should I do each day, what kind, how many sets? etc.