Fold

This is sometimes also referred to as “punching down” the dough or deflating it.  To do a fold, think of the lump of dough as a square.  You grab one side of the square and stretch it out and then fold it over the entire square. Now you grab side #2, 3, 4 and do the same thing.  In other words, you’ve stretched and then folded the dough over itself four times. This strengthens the dough and develops the gluten.