>>8155054>thin clear set glueThat is the advice for an expert (which you clearly aren't) or a 3rd worlder that has no access to proper materials.
By that he means a water-soluble glue that dries perfectly clear, doesn't shrink or crack or mess with the decal medium in any way. If you are not a glue expert you will have harder time finding that vs getting a proper decal setting solution.
Personally I used to use Mark Setter for everything until I tried Tamiya decal adhesive and I never went back. It is the best.