the middle and top of the knee cap, when you are standing straight legged. when you bend your knees and move into a ‘hockey stance’ the pant should slide up to fall in line with the top of your shin pads.
compare your height weight and age and waist size to the charts provided to find your best fit. if you are looking at a “tall” version of a pant, the waist size on the chart will be accurate, however the length will represent that of the next size bigger. 