Base coat your walls with flat latex interior paint using a paintbrush and a paint roller. Use a paint color that is lighter than your chosen topcoat. Repeat with a second coat if needed for complete coverage. Allow the paint to dry thoroughly.
Cut off the handles from plastic grocery bags and discard them. Cut the sides of the bags apart, giving you two pieces. The pieces do not need to be exactly the same size and the edges do not need to be straight. This project uses a lot of bags, but you can cut more as you go.
Mix 3 parts latex glaze with 1 part of your chosen flat latex interior paint for the topcoat. Pour the mixture into a paint roller tray.
Roll your paint roller in the mixture, saturating the roller. Paint your walls in small sections. Roll the mixture on the wall in a space approximately the size of four plastic bag pieces.
Wad up and wrinkle the plastic, then shake out and lay flat. Do not smooth out the wrinkles. Lay the flat bag pieces on the wall over the rolled paint. The glaze will allow you to move and work with the plastic. Firmly press the surface of the plastic into the paint and create more wrinkles on the surface with your fingers. Peel away the plastic to reveal the leather-textured imprint. The lighter base coat color will show through the topcoat. Discard the plastic. Repeat the process over the entire surface of the wall.