Q: how do i use my redeem points instead of my credit card

Hello Kristi,

It sounds like you have credits on your account but you are prompted to enter your credit card info. This is normal, to cover any charges that may go beyond the credits in your account.

Order of iTunes billing methods

When making purchases, content credits are used first, followed by Gift Certificate, iTunes Card, or Allowance Account credits; your credit card or PayPal account is then charged for any remaining balance.

From: iTunes Store: How iTunes Store purchases are billed

          http://support.apple.com/kb/HT5582

You may be able to set your payment method to None in your billing info:

iTunes Store: Changing your payment information

http://support.apple.com/kb/ht1918

Change your payment information on a Mac or PC

1. Click to open your account in iTunes (you may need to sign in with your Apple ID), or follow these steps:
   1. Open iTunes and click iTunes Store.
   2. Click Sign In and enter your Apple ID.
      
   3. Click your Apple ID and select Account.
      
2. From the Account Information page, click Edit to the right of Payment Type.
   
   You can see the payment methods that the iTunes Store accepts in the Payment Type section. If you want to remove the payment method, select None in the Payment Type section. See what to do if None isn't showing or you can't select it.
3. Change your information and click Done.

Thank you for using Apple Support Communities.

Regards,

Sterling