Some may argue with me here, but when I did mine I used modeling clay. Take off the head, put a ball of modeling clay on top of the piston at the edge, bolt the head back on and torque to spec. Next you will gently move the starter to get the piston to and past top dead center. I wouldn't crank on it, because you could potentially send modeling clay into your ports, or bottom end or whatever nightmare you can think of. Not likely, but I don't recommend it.
Take the head off, then measure the clay.
I would not be surprised if you had a squish of .95, mine was .85. You will be floored at the diffference. My throttle response rocks. Bike runs better, easier to jet, more power, no detonation.