I've done 2 signature quilts but I just had people sign the muslin and then I figured out a pattern to work with them. I didn't even know I needed to stabilize the muslin and they all turned out just fine, so maybe if it is already quilted you won't need any further stabilizing beyond a hard, flat surface. I'll be watching to see if anyone has any great ideas cuz I'd love to have the quilt finished and give it as a gift right after the event...but I did heat-set the signatures, so maybe I would have to take the quilt home and do that or have the recipient do that.