Using Masking Tape

Medium-adhesion Painter's Mate Green tape is a useful decorating tool for creating faux tile patterns, stripes, or borders. It won't damage paint that's over a month old, and it peels off cleanly after eight days, even after being left in full sun. About $4, Painter's Mate Green

TOH Tip: "Masking tape is not a permission slip for sloppy brushwork. The less paint you get on a tape, the easier it is to remove without making a mess."
—This Old House master carpenter Norm Abram