Prepare
Sand, fill, undercoat
On sound, previously painted woodwork, sanding with 180 grit is enough to break the shine; on bare wood, sand with 120 then 180 and apply our Multi-Surface Primer in the tone matched to your colour (white, light or dark): a deep shade such as Downing Street covers in two coats over a dark undercoat, four over a white one.
Fill nail holes and the open joint between skirting and wall with acrylic caulk, smoothed with a damp finger, and let it dry before painting. Knots in resinous softwood need a dab of knotting solution, or they will bleed yellow through a pale colour.