You can purchase a clip card below. If you do not have an account yet, first create one in the next screen (sign up).
Once you have purchased the clip card, you will receive credit in your account. When you log in, your credit will be automatically used for bookings. Please note: that your credit is only used when making a booking for one person. If you want to reserve for more people, you will need to make multiple bookings. The credit is valid for one year from the date of purchase.