You can sign up for a festival just like any other event. But there are several differences between festivals and regular shows. For one thing, at multi-day festivals you usually need to arrive the day before the music starts (especially if it is a camping festival). You also will need to provide a credit card as a deposit. If your plans change and you need to cancel, you will need to do so at least two weeks in advance of the festival, or your card will be charged the price of a general admission ticket.