A good glue for lifting decals....

[awilson40]

I just tried 3M 'Plastic and Emblem Adhesive' PN 08061 to
stick the edges of some lifting graphics. Seems to work great.Its clear and runny so use just a bit then tape the decal down for about 30 min. You can get it at most auto stores.

 

[Dennis Meyers]

I have also heard that clear fingernail polish works well. I've never tried it myself, has anyone out there used it?