Make sure your surface is clean and dust free.
Wallpaper can be applied to smooth walls and dry walls.
It must be in good condition, any holes, cracks, mildew has to be fixed before wallpaper installation.
Make sure the paint on your wall is water based and in good condition.
Your wallpaper will not stick on any surface that is oil based or silicone based.
Walls painted with gloss or semi-gloss paints should be sanded to dull the surface.
All sanded surfaces should be primed before hanging wallpaper, and any stains like grease, grime, or adhesive
residue from a previous wallpaper should be cleaned and primed with a stain killer or primer.
Wait at least 2 weeks after you have painted before applying your wallpaper.