I have two layers on, it looks halfway decent the way it is. The problem I have is that by the time this second layer is ready to wet trowel, I'll be long asleep. Is it ok to put another layer on after it's dry, and then wet trowel that, or does it "have" to be done on this layer? I should mention that the current set is pretty thin. I either have an uneven wall, or I really did a poor job in spreading it out properly. I pulled off about 4 layers of wallpaper, and ended up with some sort of mix between cardboard, and MDF, not quite 100% either, I guess. It kind of rolls like an eraser when wetted. I did put a bonding adhesive on first. But again, it really doesn't look too bad as is. This is in my own home.