Changing the colour of leather can be challenging because leather is not a porous material compared to other fabrics. Leather is also expensive, so mistakes can be costly if the colour is not applied correctly. There are professional leather dyes that change leather from brown to black, as well as other materials that help with the dyeing process. Luckily, making a colour darker is much easier than making it lighter or brighter.
Apply leather stripper to the leather product you want to dye. Put it on a cotton cloth and rub it all over the item. Use a toothbrush for any areas that are hard to get to. Give the stripper time to evaporate, approximately 10 to 15 minutes.
Put professional black leather dye on the item with a dye brush. Apply it evenly with long strokes. Allow approximately 30 minutes for the leather dye to dry. Apply another coat after the first has dried to make the item blacker and more even. Allow to dry. Apply a final coat if the item is not the colour you desire.
Place the item in an area where it will not be disturbed for a few hours so that it can dry completely. Buff with cotton rags or apply a black leather polish for a shinier finish. You can also put on a neutral-coloured sealer to keep the dye from rubbing off. Finish by buffing the item with cotton cloths.