proper way of aiming when stand up

i wanna ask the proper way to aim the shot while in a stand up..i usually line up the shot when my right eye and my right leg although my both eyes are open i more use the right eye to align the cue ball to the object problem when an hour or more i play i fell strain or pain in my right eye,,,i try terry and nics says in this furom that you have to align the shot like use your nose middle body and the line of aim runs between your right and left foot..any advice here please a true and right way to do the right thing to improve,the game that i love any suggestion is welcome and thank you some coaches here please help and others player who play a high LEVEL give me some idea :D

proper way of aiming when stand up