Setting up an event with Multiple Performances is easy!
Simply create a Single Day Event for your opening night. Then after selecting to create a new event, choose Copy Another Event. (To see how to Copy another event, go here: Copy An Event)
Tip: Make sure you remember to change the dates to reflect that show. Your Seating Chart, Ticket Types, and everything else will copy with the event, but you will need to change the date that ticket sales end.
Tip: You have the option to change the event name if you'd like, to call out details like a matinee.