Hanging wallpaper may seem simple, but in practice it requires significant planning and finesse to make it look professional. To start, you need to get an even application of wallpaper paste across all of your wallpaper, which requires experience and large pasting tables to get right. You also need to plan out your design and match it exactly so that you don’t have imperfections in the finished product. It’s often better to hire a professional wallpaper hanger who can get the job done properly for a clean, smooth finish.

Once again, contact with moisture is the culprit here, though water-resistant varieties of wallpaper are less likely to become wet and develop mold. Using a high-quality exhaust fan or dehumidifier and leaving the doors or windows cracked after bathing will keep this issue at bay. 

If you need a stronger magnetic surface, or you need to use a different type of paint in the room (like waterproof paint in a damp basement), there are other accessible options. You could fit a steel panel over the wall, try magnetic wallpaper, or apply chalk paint instead. 

If you want an inexpensive shortcut, hang a pinboard or chalkboard on your wall. These removable options are ideal if you’re a renter who can’t repaint or plan to move in the near future.

It’s possible to hang your own wallpaper, but the process is tedious and potentially frustrating, and it can be challenging to get seams to line up and look clean and professional. Plus, depending on the type of wallpaper you’re installing, using too much or too little adhesive could cause damage to your drywall or plaster, peeling, and bubbling in the final product. It’s usually a better idea to hire a professional wallpaper installer to do the work for you, as the relatively low cost is justifiable, if only to avoid damage to your walls.