Storing data for page in twig I'm using craft-stripecheckout to accept payments on my site, but want to email the user with the custom fields after they have been redirected.

Easiest way to describe this is below:

Page 1 - User is asked for payment amount and other custom inputs such as age.

Page 2 - Confirmation of details is shown, and Stripe payment button appears.

Page 3 - User is redirected here via the plugin after payment is completed. this is when the email is sent with custom fields, such as age

What is the best way to store all of the POST data, and use it again on the confirmation page?
I'm not exactly sure how this plugin works, but in general the best way to do this is to rely on Webhooks.  You can listen for charge.succeeded events and send an email when those occur.  If you're not a programmer, you can always use something like Zapier or IFTTT to do this too.

:)  Hope that helps!