i use the spray and pins also, just make sure to open the window and don't just stay there and do the whole thing at one time, do a little, take a break and walk outside for a couple of minutes then go back and do some more. your back will appreciate it too. just use a light spray on the backing then put the batting on top and a lite spray on it then put on the top. it takes a while to get it all done but it's worth it.