You don't HAVE to...but I do recommend making the dough a day in advance if you can–it really helps the flavor of the dough develop. Again, it’s *not* necessary. You can definitely make this dough and bake it same day! Allow the dough to rest overnight in the fridge after you let it rise and separate it into two balls. Let the dough come to room temperature before using it. This takes a few hours for me in my kitchen, but I’ve also definitely left it out for longer!