On the neck, the bolt would be at the top, dead center, screwed down inside the neck. Loosen it about 5 full revolutions. Then take a hammer and tap it back down. Lift the handlebar to desired height, and hold it there 'til tight. Also while it's a little loose turn it clockwise/counter clockwise, to make the bar straight (while holding the front wheel) before fully tightening. Then your done! Glad to help. Best wishes to you.