I've had good luck using Testors Acryl acrylic paints to simulate distressed leather. Testors Acrylics are thicker and heavier than craft paints such as those found at crafts stores such as Michaels, Jo-An's and Hobby Lobby. I apply them, then let them set for a few minutes and brush them some more to introduced texture. As they dry they will crack in places and take on a generally worn texture. Then I highlight the texture by applying a contrasting wash, usually a dark one. For a smoother texture simply apply the paint in thinner coats and let it dry more thoroughly between coats, reserving your texturing strokes for the final coats. The same technique can be used using crafts acrylics but those paints are thinner and don't cover as well so the process takes much longer and is less dramatic when done.
Here are a couple of examples: