Other than shooting your bow, to get your aim on, What you need is drawing exorcise. What I used to do was use a bungee cord, firmly attached, so as to not come loose while drawing or holding. Then place your bow hand against the wall and draw and hold the bungee. Do it until you are tired, but don't over do it. You can use the braided covered bungees. They will be more elastic. When you feel you are getting more developed, switch to the black rubber. They are less forgiving and will give you even more workout. Using your bow to do this is just more of a chance at wearing out your string sooner than need be, and bungees are cheap.