How to Paint a Room

Painting a room is one of the highest-impact, most beginner-friendly renovation jobs — but the difference between a patchy weekend and a crisp, professional finish is almost entirely in the prep and the order you work. This guide walks through the whole process, from measuring up to the final coat.

What you'll need

Before you start, work out your quantities so you only make one trip to the store. Drop your room dimensions into the Paint Calculator and it returns the paint and primer plus the consumables people forget. A typical kit:

• Paint — enough for two coats (most colours need them).
• Primer — for bare, patched, stained, or colour-changing walls.
• Painter's tape, drop cloths, and a putty knife with spackle for patching.
• Brush (an angled 2–2.5 in sash brush) and a roller frame, covers and tray.
• Sandpaper, a damp sponge, and a roller extension pole for ceilings.

Step by step

1. Measure and calculate. Measure the wall perimeter and height, count doors and windows, and get your paint and supply quantities. Buy a little extra for touch-ups from the same batch.
2. Clear and protect the room. Move furniture to the centre and cover it, take down switch plates and outlet covers, and lay drop cloths along the walls.
3. Clean and repair. Wipe walls to remove dust and grease, fill nail holes and dents with spackle, let it dry, then sand smooth. Clean surfaces hold paint far better.
4. Tape the edges. Run painter's tape along trim, baseboards, window frames, and the ceiling line. Press the edge down firmly so paint can't bleed under it.
5. Prime if needed. Spot-prime patches, or prime the whole wall for big colour changes and bare drywall. Let it dry fully.
6. Cut in the edges. With your angled brush, paint a 2–3 in band along the ceiling, corners, and trim — the areas a roller can't reach cleanly.
7. Roll the walls. Load the roller and work in overlapping "W" or "M" shapes to spread paint, then finish with light, straight passes top to bottom. Keep a wet edge so you don't get lap marks.
8. Apply the second coat. Once the first coat is dry to the touch (check the can for recoat time), repeat the cut-in and rolling.
9. Remove tape and reassemble. Pull the tape at a 45° angle while the final coat is still slightly tacky for the cleanest line, then replace covers and furniture once dry.

Pro tips for a clean finish

• Work top to bottom: ceiling first, then walls, then trim last.
• Keep a wet edge and don't let sections dry halfway through — that's what causes visible lap marks.
• Don't overload the roller; two thin coats always beat one thick, drippy one.
• Box your paint (mix all cans of one colour into a single bucket) so the shade is consistent wall to wall.
• Buy from one dye lot and keep the leftover labelled for future touch-ups.

Common mistakes to avoid

• Skipping prep — painting over dust, grease, or unpatched holes never looks right.
• Forgetting primer on bare drywall or dramatic colour changes.
• Buying paint for one room when the whole project needs more — calculate every room up front.
• Pulling tape after the paint has fully cured, which can peel the new finish.