Wipe up spills immediately: Spills and splatters can leave stains on the walls, so it's important to clean them up as soon as they occur.

Clean surfaces regularly: Kitchen surfaces, such as countertops and cabinets, can transfer grease and grime to the walls. Regular cleaning can help prevent this buildup and keep the paint looking clean.

Use a splatter screen: When cooking, use a splatter screen to help prevent grease and food from splattering onto the walls.

Use a grease-cutting cleaner: Grease and grime can be stubborn and difficult to remove from painted surfaces. Using a grease-cutting cleaner can help to remove these substances and keep the paint looking clean.

You can purchase from a wide range if cleaners like these here.

Avoid using harsh chemicals: Harsh chemicals can damage the paint and leave behind residue that is difficult to remove. Instead, use a mild detergent and water to clean surfaces.

Protect surfaces from heat: Hot pots and pans can leave behind scorch marks on the walls. Consider using a trivet or pot holder to protect surfaces from heat damage.

Repair any damage promptly: If there are any dings or scratches on the walls, repair them promptly to prevent dirt and grime from accumulating in those areas.