Use this stripe link:
https://buy.stripe.com/28ocQJfbE2rG65O4gh
Prepopulate with email address referred by as the promo code if the used one
https://buy.stripe.com/28ocQJfbE2rG65O4gh?prefilled_email=jojo%40exxonmobile.com&prefilled_promo_code=DiamondLiz
Pay for their first year membership