I've cut and dry fit about 120' of trim for my basement. I've done quite a bit of painting but never trim not on the wall. Any suggestions ? Brush, roller, sprayer? I'm using a semi-gloss paint. Any lessons learned would be appreciated.
I would use a brush. A roller could be sloppy and a sprayer would waste paint.
A brush will give you better control. Some others with experience with a sprayer may line up the trim with the pieces close together on the garage floor with sheeting underneath and paint it that way, but they have to watch out for applying too much.