NOTE:Please consider 3-5% cutting loss and purchase enough tiles at a time to make sure they come from the same batch to avoid slight color difference.Use a level or chalk line to create at least one vertical and one horizontal reference lines to guide tile placement.Reinforce with a laminated roller after installation.You can caulk the edges of tiles and gaps between tiles to improve the waterproof performance, spread caulk/glass glue in the seams with a gloved finger.The new painting walls need to dry for 3 weeks, make sure the wall is completely dry and dust-free.For rough surfaces and heavily textured walls, please follow the instructions:Sand the surface with sander or spackling pasteClean the wall with a damp clothWait until the wall is totally drySpray the adhesive more on the joint area on both wall and tiles