Professional painters spend more time preparing than painting. Skipping prep is the main reason DIY paint jobs show bumps, flashing patches and peeling. These seven steps make the difference.

Safety check for older homes

Homes built before 1978 may have lead-based paint under newer layers. Sanding or scraping it releases hazardous dust. Test with a lead test kit or hire a certified professional before disturbing old paint, especially if children or pregnant people live in the home.

1. Clear and protect the room

Move furniture to the center and cover it. Lay drop cloths over the floor; canvas is less slippery than plastic. Remove outlet covers, switch plates and wall hardware, and keep the screws together.

2. Clean the walls

Paint doesn’t stick well to dust, grease or grime. Wipe walls with a damp cloth and mild detergent, especially in kitchens and near light switches, then let them dry fully.

3. Fill holes and cracks

Use lightweight spackle for nail holes and small dents, and joint compound for larger repairs. Slightly overfill, since compound shrinks as it dries. Larger holes may need a mesh patch.

4. Sand smooth

Once dry, sand patches flush with a fine-grit sanding block. Lightly scuff glossy surfaces so new paint can grip. Wipe away the dust afterwards.

5. Caulk gaps in trim

Run a thin bead of paintable caulk where trim meets the wall and along baseboards. Smooth it with a damp finger. This one step makes a room look far more finished.

6. Prime where needed

Spot-prime every patch, or it will show through as a dull spot (called flashing). Prime the whole wall for new drywall, stains, glossy surfaces or big color changes. A stain-blocking primer helps with water marks and smoke stains.

7. Tape the edges

Apply painter’s tape along trim, ceilings and anywhere you want a crisp line. Press the edge down firmly. Remove the tape while the final coat is still slightly wet for the cleanest line.

Before you start painting

Make sure you have enough paint for the whole room from the same batch. Our Paint Calculator tells you how many gallons to buy, and the guide How Much Paint Do I Need? explains the math.

Key takeaways

• Clean, fill, sand, caulk, prime, then tape.
• Always spot-prime patches to avoid flashing.
• Test for lead before sanding paint in homes built before 1978.