A standard sheet of plywood is 1.22 x 2.44m and weighs anywhere from 11.3 to 38.5kg, depending on the thickness. The dimensions make a sheet awkward to carry by yourself, even if you can handle the weight. Make it a bit easier on yourself with a length of rope.
All you need to make carrying sheets of plywood a bit easier is a 6.1m piece of rope. Tie the ends together to form a loop, hook the rope around two corners of the sheet and grab the middle of the rope like a handle, using your body to brace the weight.
One more tip: the video above uses a simple knot to join the two ropes, but that's not the best choice. Instead, use a double fisherman's knot for a stronger connection.