I just saw an episode of Sewing with Nancy that had a great idea.
She turned the top hoop over to the wrong side, put strips of double stick tape on the wrong side.
She then centered the hoop over the area (in this case a quilt block) to be stitched and pressed it down. The hoop sticks to the fabric so she could slide the bottom hoop under everything and press the top hoop into the bottom. Ready to put in the machine.