Gluing hardwood edging to plywood has never been one of my favourite tasks. It’s always tricky to keep the edging from slipping while tightening down the clamps. So to help hold the edging in place, I made some clamping blocks. These blocks have a shallow, wide groove on one side that's sized to just fit over the edging and plywood, see drawing. This holds the edging flush with the plywood. To prevent the blocks from getting glued to the work piece, I apply wax to the surface of the blocks before using them.
Ted's Woodworking - Guide eBook