Summarize this article:

If you spill liquid onto your suede jacket, use a towel or cloth to gently blot as much of the liquid you can. Make sure to do this as soon as possible. Be careful not to press the liquid into the suede. Instead, gently dab at it to soak it up.  After the liquid is dry, use a suede brush or eraser to remove the stain. If you leave it, it will soak into the suede and permeate the fabric. Though you shouldn’t use use water for stains on a suede jacket, you can treat water stains with water. Dampen a soft cloth and run it over the jacket, or use a spray bottle to lightly mist it. Make sure to only use a light layer of water and that it is evenly spread over the jacket.  Soak up the water with a sponge or a paper towel. Use a suede brush to freshen the nap afterwards. Suede jackets may end up with sweat stains around the collar or cuffs. Try removing these stains by sprinkling a thin layer of cornstarch or cornflour over the stains. Leave this overnight. Remove the cornstarch with a suede brush. The cornstarch should have soaked up the oil or sweat.
Blot any liquid stains. Clean water stains by dampening the jacket. Try cornstarch on oily stains or sweat.