I would imagine that the external button will release the cranking handle from it`s locked spot,allowing the canopy to be pushed open from outside. From inside ,the crank is turned in either direction,until it is open as far as you want ,and then released to `spring` into the nearest hole. It would be best if it was chain operated rather than cables ,which can stretch,either due temperature changes,or forceful cranking,but as it`s a WHL product,possibly cord.....See a Jet Provost 3/4 for something similar.