Unzip the downloaded file ( DirtyTilesWallsPart1_ASW.zip ) and move the contents into your Electronic Arts > The Sims 4 > Mods folder.
Includes 14 swatches of dirty wallpaper and wall tile patterns. Dirty Tiles & Walls Part 1 at Annett’s Sims 4 Welt
Access the Dirty Tiles & Walls * Part 1 on Patreon or through Annett's Sims 4 Welt blog. Unzip the downloaded file ( DirtyTilesWallsPart1_ASW