Wash the item before painting it, if possible. Use the method you normally use, be it in a washing machine or by hand. If it's a throw pillow you can't wash, shake the dust off vigorously; fill a spray bottle with half cold water and half white vinegar and shake. Mist the pillow in this naturally-deodorizing spray and let it air dry.
Lie your piece of fabric or garment on a flat work surface and smooth it out. Shake your fabric paint well. Dip a 2-inch brush in the jar and shake the excess on the rim of the jar, allowing the drops to fall back in.
Apply your first stroke to the top-left corner of the item, bringing your brush down as far as the paint allows. Re-dip your brush in the silver fabric paint and finish your column stroke of silver, creating another overlapping stroke. Continue in this manner until you cover the entire object. Allow it to dry overnight.
Turn the object over or inside-out and iron it the following day over medium heat. This helps set the fabric. If you can't do this, like for a pillow, hold a hairdryer over it for 35 to 45 minutes over high heat to set the paint.