To remove an air bubble, gently pierce it with a needle or the tip of a box cutter. Press the air out carefully to flatten the wallpaper. For the best results, you can also use a glue gun to inject a small amount of glue into the bubble before pressing it down.
Important Note: On wallpapers with solid color areas, the hole may be slightly more noticeable compared to patterned designs, such as a forest motif.