Align the second strip with the first.

This can be easier or harder based on your chosen pattern: For example, a ‘random pattern’ will be the easiest to align and cause the least wastage, whereas a mural or pattern that needs careful alignment may require additional rolls of paper.

Do a dry fit before removing the backing by holding the second strip up against the first one on the wall
Once the design is aligned in your dry fit, cut the second piece at the top so you'll know where to place it (including extra inches for overhang) before applying adhesive.
Repeat the adhesive process with the second piece, using the seam roller to ensure a good adhesion between the two pieces along the vertical seam.
Repeat for the remainder of the wall, remembering to smooth the surface as you go with the smoothing tool.
Replace electrical plates and other items you removed and you're done!

Are you ready to install your wallpaper?