1. Cover up.
Protect the floor, and any furniture you can't (or don't want to) move, from paint splatters and spills. For the floor, choose fabric drop cloths instead of plastic ones, as plastic can be slick under your feet or, worse, the ladder.
2. Start with a fresh surface.
Paint won't adhere as well to a dirty surface (think fingerprints, soot, dust, cobwebs), so use a Swiffer-type mop to dry-dust the walls first. Swab down any extra-grimy parts with a wet sponge or cloth; you may need a ladder to reach up high.
3. Prep the borders.
Remove outlet and light-switch covers, and tape off any areas you don't want painted — such as moldings, baseboards, or window frames — with blue painter's masking tape or green Frog Tape (from $6, Amazon.com). The Good Housekeeping Institute tried the latter on a smooth wall and found that it makes a crisp line and doesn't let paint bleed through.
4. Skip a step.
Typically, painting over a dark wall with a light color (or covering stains) requires a coat of primer and two coats of paint — and at least six hours of drying time. That's why GHI recommends Benjamin Moore Aura ($55 per gallon, benjaminmoore.com), a self-priming paint (it's a cost-effective option if you were planning on buying primer). Going from light to light? You can get away with two coats of good-quality regular paint.
Now you're ready for the main event: With an angled brush or a sponge tool, paint a two-inch swath around the edges of woodwork and the ceiling, which should be taped off (see step 3). Then fill in the central unpainted space using a paint tray and a roller (1/4-inch nap for smooth surfaces, 3/8-inch nap for semi-smooth, or 5/8-inch nap for rough — the wrong tool will apply too much or too little paint) in overlapping W- or M-shaped strokes for the best paint distribution.
For easier cleanup later, try a quick-release frame-handle roller, like Shur-Line's ($8,shurline.com). Other worthy investments: an extension pole, so you can stash away the ladder after the edging step; a paint-can opener; and a pour spout to lessen mess. Let the first coat dry at least a couple of hours, then coat again. (Between coats, cover the tray and brush with plastic wrap touching the paint surface, and refrigerate.)
6. Wrap it up.
Rinse your paintbrush and roller (if you don't toss it) under a faucet until the water runs clear. Decant the tray's leftover paint back into the can; seal the can tightly by placing a paper towel over the lid and tapping the lid edges with a hammer. Rinse the tray. Once the brush's bristles are totally dry, slip the brush back into its original paper wrapper to keep the bristles from fanning out, or try this DIY fix: Fold a thick piece of paper around the bristles; tape to secure.
7. Leave no trace.
Have a moist rag handy to wipe fresh splatters. Scrape off dried drips with a credit card or plastic spatula. Remove masking tape before you call it a night, pulling it off at an angle, to avoid tearing the finish.
