After you click on MAKE A PAYMENT you will be redirected to Paypal. You can set the amount there by selecting +/- in the Quantity field (price can be set in 10$ steps). You don’t need to have or create a Paypal account. Payments can be made with credit cards or Paypal. After your payment is successfull, please contact us on firstname.lastname@example.org regarding the purpose of the payment.