Place about a cup of salt and your silk plant in a paper grocery bag. Simply roll the bag closed and shake gently for 10 to 15 seconds. The salt should remove any dust particles from the silk without damaging it. Just be careful not to shake too hard, as this could break the plant.
Vacuum your plants. If your vacuum has a small attachment, you can easily run the hose over your plants and vacuum the dust. This is one of the easiest, cleanest ways to care for your silk plants. Just be sure to run the vacuum on low, and don't make complete contact with the hose and the plant to avoid damaging it. You can put nylon pantyhose around the attachment or use an attachment with a brush to protect your plant.
Dust your plants with a dryer sheet or Swiffer duster. These products are great for attracting dust without spreading it around. If you don't have access to either of these items, lightly wet a towel or washcloth and simply wipe your plants clean. If you get the towel too damp, it could possibly damage your silk.