I first decide what distances I'll be using the rifle. Based on that I select a zero distance which takes into consideration sight over bore and muzzle velocity. Once that is settled I head to the range. I'll pick a rock or clump of weed on a dirt bank, then fire #1 and watch for the dirt splat. Adjust scope accordingly. Next I'll fire #2 at paper. Adjust accordingly. Then I'll fire #3,#4,#5 for a group. Adjust accordingly. #6 will be on the money.
Some may wonder why I first shoot at a rock on a dirt bank. It allows me to be reasonably assured that my second shot will be on paper rather than the hunter who blows through a box of 7mm mag and curses that he's not on paper yet. Some guys use laser boresighters and other methods of looking down the bore.