I have tried it all when it comes to assembling your invitations. This is what I believe to be the best solution without any lifting up of any kind. It just takes time, as any assembly would. *Krylon spray adhesive
*3L repositionable permanent mounting squares, 1/2-inch x 1/2 inch
I use the spray for the invite, and the mounting squares for emblems or belly bands. Though you can use the mounting squares for the invite, you'd just have to use 6/8 of them.