Fandango, Atom and also at theater. It's very easy to do it, just create an free account on those site and follow the instruction. That's it.
You can purchase tickets at the theater, either from a person or a kiosk, and reserve that way. More recently, Cobb Daytona also sells tickets via Atom Tickets (and possibly also Fandango). You choose a seat reservation when you purchase through Atom Tickets as well.
You have to reserve your seats as you are purchasing your tickets.
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