welcome mate one of the ways ive done this is to use a dry stone wall and stand/sit about 20/30yards back an shoot at the wall an see were it hits an keep aiming at that spot an ajust the scope after every couple of shots till you get within the size of a ten pence coin or as verry near as you would like its worked for me ive done it this way from the age of 11 when my dad first took me shooting im now 26 all the best mate