Requirements:

If you intend to start by filling in holes, or if you need to paint window frames, doors or cupboards, you should first remove all handles, locks and other fittings. If there’s any rotten wood, chisel it away until you reach the solid wood underneath, and then fill up the hole with liquid timber (wood-fill). Use a paint scraper to remove any peeling layers of old paint.

The next step to make sure that the new paint adheres well to the surface is to degrease old paint layers and/or sand the surface of the wood. Use ammonia water to clean the surface, and sand it with waterproof sandpaper no. 250. Remember to wear safety goggles and a coverall to protect yourself from dust, dirt and ammonia fumes.

Surfaces that don’t need to be painted (yet), like window frames, door posts and power sockets, can be covered with masking tape. Make sure you remove the tape as soon as you’re done painting! If you leave it on too long, it’s a lot of work to scrape off all the bits of glue and tape! Finally, make sure the room you’ll be working in is dust-free.

Generally, once the preparations are done, you’ll usually apply a coat of primer first and then fill in any holes, but some brands of filler recommend doing it the other way around. Make sure you read the instructions before you start! Use white primer to paint over light colours and grey primer to paint over dark colours, but make sure your primer coat isn’t too thick.

Every filler job requires a different kind of filler:
Indoor use: holes and cracks in stone walls, foamed concrete, sand-lime bricks, plasterboard, concrete → red band or gold band.
Outdoor use: holes and cracks in walls, concrete and sand-lime brick → lime mortar plaster.
Put some filler on a broad putty knife and spread it over the surface to be filled, using controlled movements. Remove excess filler immediately. Let the filler dry, then apply an extra layer if necessary. Lightly sand the filled section.