Preparation For PaintingThere are reasons why so many of us repaint our walls every year: Painting gives a room a whole new look and feel, it doesn’t cost much to do, and it doesn’t require a whole lot of know-how. Still, it’s not a cakewalk.

If you’ve taken brush to wall before, you know the potential pitfalls: Streaks, messy edges, and spills are par for the course for the hurried or uninitiated painter. Though fixing your mistakes is usually fairly simple, it will be the last thing you feel like doing when the work is done. (Trust me.)

The secret to a professional finish lies in good prep work and a few tricks of the trade. To help you do the job right the first time, I asked some paint pros for their best advice. Here’s what to know before you start priming.

Empty Out the Room

You’ll want to give yourself plenty of space to work, advises Judy Crockett of Dave Crockett Interior Painting in Manistee, Michigan. So clear out the furniture, window treatments, and anything on the walls (this includes artwork, nails and switch plate covers).

Smooth the Walls

Scrape off any rough patches of old paint from the walls with a putty knife. Fill in holes or cracks with spackling paste, let dry, then smooth with a wet rag or sandpaper. Finally, wash the walls with a heavy-duty cleaner like TSP to get rid of dirt, grime, and smoke, Crockett says.

Vacuum Everything

Its important to vacuum everything — and that means everything: the walls, floors, ceilings, light fixtures, air vents — you name it. “Dust in the air will show up on the finished walls,” Crockett points out.

Lay Down Good-Quality Painting Tarp

It will keep any drips from seeping onto your floors.

Protect Your Trim

You have a few options here: First, you can lay strips of painter’s tape over baseboards and molding for protection that won’t damage surfaces when you peel it off. Second, you can use a paint shield to protect smaller areas — just wipe clean when you’re done. Third, you can wipe down the trim with a wet sponge first, paint as usual, and wipe away any drips with the same wet sponge, suggests John Wilder, a former professional painting contractor. “It takes [the paint] all back, way faster than taping,” he says.

Prime Unpainted Walls

For fuller color coverage, Crockett suggests tinting your primer with a shade that’s close to the new wall paint color.

Do Trim Work First

As tempting as it is to start slathering on wide swaths of paint, your best bet is to get the corners and edges out of the way first. Use a 2-inch brush to tackle the job, and then cover the rest of the wall with a roller and paint tray. Wait a full 24 hours before applying the second coat. “Yes, you do need to apply two coats!” Crockett says.

Use Consistent Strokes

There should be a method to your madness, and it should look like this: “Paint in even strokes down from ceiling to floor and back up,” advises Brian Penny, a former commercial and residential painter. “Move the roller over so it barely overlaps the paint, and roll down and up. Continue until you no longer get an even coat, then backroll. This means aligning the middle of the roller with the stroke overlap and rolling up and down to smooth out any drips.”

Is this gam plan a little more labor intensive than, say, slapping some color on the walls and calling it a day? Sure. But is doing all that work now so you can enjoy a smooth, clean paint job for years to come worth it? Absolutely.