Prone Single Surface MACB.

If you strafe left and right while on the edge of a flat surface, you can enter the falling animation, similar to a standard corner boost. In this falling animation, instead of boosting off the edge like a corner boost, you can look back at where you came from to get a mid air. When you enter the falling animation, do not press any movement keys or you will not get the mid air. Another method to do this is tapping forward off of a surface while looking at an angle, this is a little safer but it requires a longer surface to do. If you are confused by this just scroll down in the post it should help.