Activate my itunes account without giving a form of payment

I searched online and came across a thread that said i should select none payment option when the section comes up requiring you to give a credit card or other form of payment to fully activate your account.
this is really annoying because i dont want to and never plan on buying anything on itunes but i cant update my mac book air now because it requires a activated account to install the updates. Should you not be able to just setup an account without having to give payment details?
and no i will not give my details. So what should I do then....?
have to manually update my mac by finding the updates online elsewhere or what?