After you mount the scope. First thing you want to do is MAKE SURE that the vertical crosshair is right in line with the bore. You want the scope to be level. There are a whole bunch of different ways of doing it, including little gadgets and such, I just eyeball it. Then you'll want to bore sight the scope. You can do it at anywhere between 25-50 yards. Take the bolt out of your rifle and set it in a firm rest. Line up the bore with a target, either by looking down the bore, or putting a deprimed case in the chamber works too, kinda like a peep sight.
then just line up the scope to the target while the bore is lined up to the target. This should get you on paper.. Now just zero to whatever range you want. Whether it be 100 or 150 or 500! That's really upto you as it depends on your preferences or what you intend to do with the rifle.