How do I set up ordering so they don't have to pay right away?

There are some payment integrations that will allow you to do this, you can check more details about the payment integrations that allow this on the next guide: How-to-Enable-Payment-Authorization

This way your users will provide their payment info and submit the form, but you will need to manually charge your users on a later date. 

Please if you have any question, let us know.