Ripping a pack means opening a package to reveal the card included in your purchase. Before you rip, the odds for all possible results will be displayed for you to review.
When you're ready, click Rip Pack. You'll then be asked how you'd like to pay:
Via Balance: This will use the funds already loaded into your account.
Via Credit/Debit Card: You'll be prompted to enter your card details to fund the purchase.