Cut your pieces of cotton fabric into about 15 x 15 squares. Iron down each side once all the way around, and then fold it over again and iron once more.
Pin after ironing
Sew around the perimeter to hold the seam in place
Pour some paint onto a piece of scrap paper or paper place. Place some cardboard or newpaper beneath your fabric
Dip the round foam brush into the paint and press onto the fabric, twisting and turning to produce an even coat. Scatter polka dots starting from the corner out, or whatever design you'd like.
After allowing it to dry fully, fold and set your holiday table! You can throw these into the wash too