Empty the room by removing all furniture, pictures, curtains, shelves and everything attached to the wall with a screwdriver.
Sand the existing walls painted with glossy paint; use fine-grit sandpaper. Lightly etching the gloss surface of the existing paint helps the primer and new paint adhere.
Fill a bucket with warm water and three to four drops of gentle dish soap. Dampen a sponge mop with the soapy water and wash the walls to remove dirt, sanding dust and grease or oil residue. Rinse the walls with a clean mop and clean water to remove left-behind soap. Allow the walls to dry overnight.
Patch screw holes, small cracks or scratches with spackle and a putty knife. Allow the spackle to dry, and then sand it smooth and level with the wall surface using fine-grit sandpaper. Remove sanding dust with a sponge dampened with clean water.
Apply an even coat of paint primer to the walls with a paint roller and smaller paintbrush for corners and edges. Allow the paint primer to dry for the time stated on the primer can.
Cover areas or items you do not want painted with painter's tape, and spread drop cloths on the floor to protect it from paint splatters.
Roll on the first, lighter colored paint with a regular paint roller. Choose two different colors within the same color palette -- one lighter and one darker -- to achieve the ideal look. Cover the areas you wish to paint with the lighter colored base coat until completely covered. Allow the base coat of paint to dry for at least four hours, or as directed on the paint can.
Pour the second, darker colored paint into a paint tray. Use a small paintbrush to apply the paint into the corners of the walls.
Attach a leather-texture roller to the paint roller, and dip it into the darker colored paint. Roll the leather-texture roller over the grooved ramp of the paint tray to remove excess paint. Begin painting at the top-most corner of the room, creating smooth and even strokes. Move the leather-texture roller as close to the corners as it will go to create the leather finish throughout.
Continue re-wetting the leather-texture roller with paint and brushing the color onto the walls until you have evenly covered the entire room. Allow the leather-textured finish to dry up to 24 hours before adding items back onto the walls and into the room.