Step 1 Make Sure your Panels are Straight
The first thing you’ll need to do is run a level line vertically to ensure your first panel is straight. Start on the second panel in and leave the panel right against the edge to do last. Walls are hardly ever square so this way you’re not depending on the wall to keep your wallpaper square. Make sure to leave a bit less than a full panel width for that last panel. You’ll be cutting excess away on that last one.