You need to pick a location with great ventilation such as outside or even a garage. Always wear eye protections while trimming. Entirely sand every piece with the program paper being attentive to gouge the wood.
After trimming all bits completely wash them down with a fresh and moist cloth. This will be really to remove the dust and grime prior to painting. Latex may be used but make an effort to use a loofah. Gently brush paint on every piece being cautious to prevent lines and runs out of the brush. Allow to fully dry and apply another coat of paint.