i get on his hand, but im stuck from there

I'm assuming that you're on the left arm.

Once you get on his hand, you can do one of two things. You can either run up to his bicep, to where the glowing spot is, and stab it, enabling you to jump to the other hand. Once on the other hand, wait for him to steady his hand, stand on it and get out your bow. Shoot the glowing spot on his shoulder, he'll reach up to hold that spot, jump onto his shoulder from there.

OR

Once on the hand, run onto his gauntlet, the forearm, and he'll start looking at his hand again. Hold on to the ring that is first, coming from the hand end, and while he lifts it to closer examine his hand, jump from the hand to a platform on near where a human's collarbone would be.

i see. and i was on the right hand, but thanks

When youre on the right hand you have to stab him twice full charge.