To pass/bump you put your left hand in a fist, put your other hand around your fist, don't go to the ball the ball comes to your arms, to be exact your forearm, and then sort of lift your arms up when you're about to bump/pass the ball, try to hit it to someone or the net. It's called passing if you hit it to soemone but if you hit it over the net that's called bumbing. Remember to NEVER swing, that will not make your coach happy.
When you set the ball you usually are gonna set it to the spiker but it's fine if you set it over the net but then that would be a perefct set for the other team to spike your ball. You use both hands, your hands should be at your face, make sure your a little bit to the side of the ball but make sure it's over your face, sort of go down and then push your arms up and out to the spiker on your team or to the other team.
When you spike the ball you only use one hand. After someone sets the ball to you, you're supposed to jump up and hit the ball with one hand, hit it over the net, use all your power and strength, and hit it towards the ground.