Lift your front foot and rear heel. Simultaneously lift your front foot and your rear heel a few inches from the ground. Your entire body's weight should be balanced on the toe of your rear foot, which is obscured from the audience's view. To them, it will look as though both feet are a few inches from the floor.
Hold the position for five to ten seconds. Any longer, and your audience might try to peek behind your front foot.
You might want to experiment with different pairs of pants to figure out which ones best obscure your rear toe without getting in the way.