The skirtings, doorframes & doors have several chipped & flaking coats of paint on them – how do I make them presentable?

The first job is to sand them with a coarse grade of sandpaper to get off the worst of the lumps and bumps, followed by a medium grade sandpaper. Next, the imperfections can be filled with Polycell Wood Flex Polyfilla. Lastly, the filled surfaces should be given a final light sanding with fine grade sandpaper. Wipe clean and paint.