In my opinion it is pretty important to follow the proper sequences if you want to end up with a good paint job. Take for example the average interior room. Here is the sequence I normally follow when painting over an old paint job:1. Prep and paint ceiling (one or two coats as needed)
2. While ceiling is drying, remove all outlet and switch covers, door hinges, locksets and windows locks.
3. Prep and paint window sash, trim, casing and baseboards. (doors can be done now or as you have time in between coats) Wash out brush while waiting to apply 2nd coat. I like to use a stiff hand scrub brush to clean the brush. It removes all the excess dried paint from the brush.
4. It is much easier to cut in the wall to the trim as opposed to cutting the trim up to the wall. Cut in a nice 3" + wide strip all around so the roller does not get close to the ceiling and apply first coat of wall color with a 3/8" nap roller cover. I like to cut in and roll it out right after so there are minimal brush strokes on the wall. Many people like to cut in a whole room first but I stay away from that method. While you are waiting for the wall color to dry it is a good idea to wrap the roller cover in Saran Wrap to keep it from drying out.
5. Cut in and apply 2nd coat of trim paint slightly overlapping the wall color, just enough to barely see it on the wall. Avoid painters tape and use a nice wide 2-1/2" or 3" angled sash to do all the cutting in.
6. Repeat Step 4 and apply 2nd coat of wall color.
7. Clean up trash, apply outlet and switch covers (and all hardware that was removed).
Stand back and admire a job well done.
