If I need to pin, I prefer using Elmer's glue.
Regarding pinning, I think one of the most important things is to choose a good quality straight pin. It should be very fine with a sharp point. I think it also helps if they are long, or at least not really short. I also like glass head pins because they don't melt if I need to iron. I tried flathead pins only once; although I think it's a great idea to have a flat head, the quality of the pins I got was terrible -- not very sharp, and not very fine.