To keep your suede curtains looking their best, you should regularly dust them with a lint-free cloth. Suede tends to be difficult to wash when it gets very dirty, and most experts recommend using dry cleaning services, which can be costly, instead of cleaning them yourself. If you want to reduce the number of times throughout the year that you need to have your suede curtains professionally cleaned, you should do what you can to keep them from getting dirty. Dusting should be a priority, and any small spots or stains may need to be taken care of as soon as you notice them.
The way to treat small spots and stains on your suede curtains typically depends on what soiled them. There are products on the market specifically designed for cleaning suede, and these may be your best bet to use on most types of stains. Regardless of what type of stain you are trying to remove, it's a good idea to test out any suede cleaning product on an inconspicuous area of your curtains first to be sure that it won't damage them. After confirming that the product won't harm your curtains, you should use it according to package directions.
If you want to try to remove spots and stains from your suede curtains at home, you may have some success with using white vinegar or a pencil eraser. Some soiled areas can be erased with an eraser, but this does not always work. If it appears that the pencil eraser is not removing the stain, you should immediately stop using it because it could damage your suede. You can also try putting a small amount of white vinegar on a damp cloth and dabbing at the stain. You don't need to rub on the stain vigorously because this will likely just rub the stain further into the fabric, which might mean you'll never be able to get it out.
After you have dusted and removed spots and stains from your suede curtains, you might want to go over them with a suede brush. These brushes are available at most stores that sell cleaning supplies, and they can help keep your suede curtains looking like new. To get the most longevity out of your suede curtains, you may need to send them off for professional cleaning at least once per year. Professional cleaners may be able to remove stains and soiled areas from your suede curtains that you either missed or were not able to remove yourself.