Having a piece of artwork or photography that hangs unevenly on a wall can throw off the entire look of a room. One trick to ensure that this doesn’t happen in your home is to purchase clear mounting squares from your local craft store.
Attach the piece of art to the wall and place a level on top of the frame. Adjust the frame so that the art is balanced according to the level. Once the piece is level, place a mounting square on the bottom-center of the frame and press it against the wall until it sticks. Thus, the mounting square holds the art in place as it sits between the wall and the backside of the frame.
Use as many squares as necessary and roll them up if need be to fill in the space between the frame and the wall. Once the frame is secure, remove the level and move on to the next piece of art. The beauty of these squares is that they provide a great sticky medium without damaging walls or frames.