Its pretty straight-forward. Keep in mind Coinbase has fees (which will be shown to you at the time of transaction - purchase) - 1.5% when using bank account (keep in mind that the bitcoin will be available AFTER some days, not right away! When i bought some it took like 5 days to come to my wallet). Credit card / debit card purchase will be INSTANT, but it has its price - HIGHER fee of 3.99%.