How do i go from having a kinda big stomach to a 6 pack?

Being "fat" runs in the family (sorry family), and so i am kinda big...thats not my excuse. Anyways, will doing crunches help me lose stomach fat as well as gimme a 6 pack? And i dont have weight sets, cept for 10 pounders, should i do pushups instead? And how many per set, and how much time in between sets, and how many sets...thanks