First, read the manufacturer's instructions. No, this is not a joke. Yes, many of them are very generic. Occasionally, specific instructions are given on booking times and adhesive recommendations. Second, tear a small corner of the material.
Paper needs more moisture in the adhesive to relax.
Non-woven backings require less moisture. The wallcovering may tear easily, revealing that it is a surface-printed paper. If the backing separates from the face, it may be a vinyl film, custom-screen vinyl, mylar, or foil. Third, check to see if the backing is prepasted by running your finger on the back or wetting it if necessary. Preferably, place the test strip in a plastic garbage bag to accelerate the wetting out.