Black plastic upper right is in place for threatening cold grey storm, each patch piece seemed as if it might be the last. This work was done as rapidly as possible.
Dampened burlap is laid on a plastic covered work area, one side is painted and that side sticks to the prime coat of cement/acrylic mix which is applied to the surface to be repaired. The cement and acrylic mixture does not need to penetrate completely. It is easier to stick the patch overhead if the patch is only painted on one side because cement is heavy and the sticky side holds immediately if the patch is lighter, without heavy material on both sides of the fabric patch.
Paint the exposed side with two or three coats when the patch material is secure.
New material bonds very well with old, completed patch will hold for years. Three year-old bonds like this show no sign of parting, patches become difficult to find after a few years.