Instructions
Visit the "Minecraft" website (minecraft.net).
Click the "Log In" button, located at the top of the page, to sign in to your account. If you do not have an account, create one by clicking "Register." You cannot upgrade to premium without first creating an account.
Click the "Buy Now" button.
Select a payment method. Payment methods include credit card, PayPal and Moneybookers.
Click the "Proceed to Checkout" button to finalize your order. Follow the onscreen directions to submit your payment. To pay with credit card, you will need to enter your name, address and credit card information. To pay with PayPal or Moneybookers, you will need to log in to your account and submit payment. Once your payment has been finalized, your account will become premium.