fold over
To crease something so that one part of it is positioned on top of another part. A noun or pronoun can be used between "fold" and "over." Hey, fold over the blanket so I can climb into bed with you.
fold something over
to double something over on itself; to make a fold in something. I folded the paper over twice to make something I could fan myself with. Fold over each sheet, and then place it on the stack.