Hanging the first strip straight is one of the most important things you can do to ensure a visually pleasing installation.
Use a plumb line to make sure your first strip and those that follow are straight. Choose an inconspicuous corner, preferably
close to a window or door. Measure from the corner to a point 1/2" narrower than the width of the wallcovering. Then, drop a
plumb line from that spot. When the line stops moving, hold it tightly at the baseboard with one hand and snap it with the
other. The colored chalk line on the wall is now your starting point. For accuracy, snap a new line on each wall. This placement
line will be where your first two strips of wallcovering meet. Note that some installers choose to draw this line on the wall
using a level.