When someone signs up for Wagn, an Sign up card is created.  So, to customize the sign-up information, you simply format the set of Account Request cards using the *structure setting.  Learn more about structure.

When an Account Request is approved, the card is changed into a User card. If you want some of the sign-up (account request) fields to show up on the eventual User card, just include the same card on the User card using structure.

Note: both the Sign up and User types may be renamed -- they'll still work.