Set up a fairly large piece of cardboard, and put a target in the middle.....the bulls eye needs to be small, as you need to shoot at the exact same point each time......shoot off a good rest of some kind.......put the cross hairs on the bulls eye and squeeze the trigger.......shoot at least 3 rounds in order to see if your getting a close group.........if you are, prop the gun up where it won't move with the cross hair on the bulls eye, and turn the scope adjustments until they line up with the pellet holes on the target........shoot again and you should be hitting the bull's eye.......
If your not getting a good 3 round group, you either need to practice the basic fundamentals of shooting or return the gun and get something more accurate......Air rifles are load of fun.....