Just pick a cylinder. With intake valve all the way open, adjust exhaust valve to zero. Rotate the engine till exhaust valve starts to open. Then adjust intake to zero. Then take a compression test on that cylinder.
It means you rotate the engine until the EXHAUST valve just starts to OPEN, an you adjust the intake on that cylinder. Then you rotate until the INTAKE opens all the way and is almost CLOSED and adjust the exhaust on that cylinder
Remember the cam only rotates at half crank RPM so at "one" TDC no1 valves are closed and on the next rotation to TDC both no1 valves are both open
