How can I test credit card payments on a form

Hi - I think I've followed the tutorial correctly to set up both a purchase order and credit card payment form on my registration page, and I can easily test the purchase order part, but without using a credit card - is there a way of testing that element of the form before launching it? 

I have checked your form and I can see that you have provided 2 options. PayPal and Purchase Order. For purchase order, you won't need a card to test.

And for the other option i.e. PayPal, you can test it in the sandbox mode. Here is a reference guide for the same: How-to-Test-your-PayPal-Payment-Form

Let me know if you have any questions.