How to Hang Wallpaper Around a Window
Depending on the type of wallpaper you are hanging, you will either paste the paper or the wall itself. For most traditional unpasted wallcoverings, you will apply adhesive to the paper and “book” the material before hanging. For non-woven wallpapers, the manufacturer will often recommend pasting the wall. The wallcovering instructions will identify the option best suited for your paper.
Once you have identified the proper hanging method, tack your wallpaper to the wall over the window. Reposition the material as needed to keep the paper aligned neatly or to match the pattern to a previously hung strip. Allow your wallpaper to drape over the window. The excess paper will be cut away with a series of relief cuts.
With the wallpaper draped over the window, feel for the top corner of the window casing. Then using a sharp pair of scissors, make a diagonal cut upward toward the corner. The cut should allow the paper to lay flat against the side and top of the window casing.
Lightly press the wallpaper against the vertical edge of the window and feel your way to the bottom corner. Make another diagonal cut, this time downwards, towards the corner of the window casing. With the relief cut completed, the paper should be able to wrap around the side and bottom of the window.
Trimming the Excess
Begin by roughly cutting away the excess paper over the window. Clean up any excess paste that may be on the window glass. Smooth the wallcovering and double-check to make sure your seams are tight. Then, with your smoothing tool, firmly press your paper along the edge of the window casing.
Using a sharp snap blade knife and a trim guide, cut away the excess paper at the ceiling. Continue to trim the paper along the top and sides of the window casing. Be sure to change blades frequently. This will help keep the cuts clean and reduce the chance of tearing the paper. Once you have trimmed the paper around the window, wipe down the window casing with a damp rag to clean up any excess wallpaper paste.