Set up target about 50 to 75 yards out. Brace rifle against something so it wont move. Aim at center of target and shoot, do this 2 or three times. Go look at where you hit the target and adjust sights/scope...windage/elevation accordingly then try it again. Repeat until you hit the center of target with consistency. You dont need any fancy gizmos just a little time.
Shoot once, adjust the scope to put the crosshairs on the hole. Lather, rinse, repeat. You should be pretty much on within three shots.