I'm just after some advice on the best way to attach a background. The guy in the LFS said there was some type of glue in the US which they had, unsuccessfully been trying to import for a while. I'm in the UK by the way.
If you mean a printed one try vaseline, some sort of cooking oil or liquid soap and water. Just make sure you spread it out evenly and smooth it all down on the back so you don't end up with obvious patches like I have!