Use the tape McNett sells that's clear on a white backing, I do not know the name, but it repairs clear. Use on the underside, use SeamSeal, then leave the tape on until it decides to part with the fabric would be my recommendation. Also, you want to make the patch tape oval without corners to lift and ruin your repair. I have repairs made this way that are over ten years old because I did not use square edges on the tape IMO.