Well tiles are considered the best option but only if installed properly. Just keep on mind that the walls should not only look good but also endure warm, moist conditions. Select material that are resistant to mold and clean easily. You can have a regular plaster drywall and cover it with semi-gloss or high-gloss paint. These paints will allow the walls to be wiped clean with a damp cloth. Avoid matte paints, which cannot be easily cleaned.

You can chose to install Cement backer board which is as good as traditional drywall, but is more durable. It can endure water and moisture and can prove to be quite stable. However remember to cover the boards with a water-resistant covering, such as polyethylene plastic or vinyl wall coverings.