Vacuum the rug thoroughly to remove all dust and particles that might interfere with the paint's ability to bond to the rug. Remove all furniture from the rug.
Lay the rug out flat on a large sheet or drop cloth. Rugs are porous and the paint will soak through and ruin the floor beneath if you don't take precautions.
Lay down tape or stencils to create the pattern and design that you have chosen for your newly painted rug. Make sure that stencils are securely taped so that they lay flush with the carpet and will create a seal so that the paint won't seep under the stencil.
Pour the paint out onto a paper plate. Use a different paper plate for each color to prevent unwanted mixing of colors.
Use a sponge to lightly stamp the paint onto the rug. Use a thin coat to prevent the paint from seeping under the tape or stencil. Allow the paint to dry to the touch and apply additional coats as necessary until you get the color you desire. Allow the paint to dry for two to three hours.
Carefully remove the tape. Pull slowly at a 15 degree angle to avoid peeling the paint.