I've created a sale for event registrations in order to give an event ticket discount. However, I'd like to offer the cheaper tickets to my customers first so I want them to use a promo code, like you can do in the shop.

The problem is that the input field for a promo code is only visible if you first proceed as follows: You register for the event, and then you go backwards in the shopping menu (Review Order > Shipping and Billing > Payment > Confirmation) from Shipping and Billing to Review Order. When registrating to an event, you normally never come to the Review Order page, but only there you can use the promo code for event registration.

So my question is if there's an easier way to do this? It's not very intuitive to go backwards in the shopping process.