Much easier to cut in walls to trim than trim to walls.If painting new wood trim, always prime with oil base primer. This is definitely old school. Today's painters never heard of such and sure not getting a luxurious finish.Next let primer dry 24 hours and sand using 220 grit sand paper. Next caulk and putty. I like using an oil base gloss finish paint applying two thin top coats and letting dry 24 hours in between coats. A company sales a brilliant interior oil base paint.The MUST HAVE TOOLS.:1: 5 in one. Do not begin a job without it. It's like a carpenter showing up without his hammer.2: 1- 3" Black China Bristle paint brush. Beginners maybe 2" 1/2.3: 1- One gallon of paint thinner.4: 1- Pint of Penetrol .Penetrol is a paint conditioner to be added to oil or alkyd based paints to make painting flow more smoothly. Penetrol reduces brush marks and leveling problems while improving penetration and adhesion of the paint.NOTE: When using Penetrol only 2-3 cap full to 1/3 gal. of paint. When thinning oil paint remember be careful. Do not add to much thinner. Whats to much? Paint has body and thinning takes this away. A good rule, after mixing the additives pull the paddle or stick out of the paint, the paint should flow off the paddle like pouring liquid dish detergent. If over thin add some paint that's why I only mix up a 1/3 to 1/2 gal. at a time unless I'M spraying.