Roll Paint Along the Edges for Consistent Texture
Corners and areas next to trim that are painted only with a brush have a noticeably different texture than the surrounding paint. To ensure the finished texture will be consistent in these areas, brush on the paint, then immediately roll it out before the paint dries.
Use a 3-in. roller with a nap that's the same thickness that was used for the rest of the wall. Roll as close as you can without bumping the opposite wall or slopping paint onto the trim. Finish brushing on the paint and rolling it out in one area before moving on to the next section.
Prime and Texture Wall Patches to Avoid a Blotchy Finish
Freshly painted walls often look blotchy. The color is uniform, but the sheen isn't consistent. This usually occurs over the holes and cracks you patched with a filler or drywall compound. The porous fillers absorb the paint, dulling the surface (a problem called 'flashing'). When light hits these dull spots, they stick out like a sore thumb. The smooth patch also stands out in contrast to the slightly bumpy texture of the rest of the wall. A quick coat of primer is all it takes to eliminate flashing and texture differences.
Primer seals the patch so paint won't sink in and look dull. To match texture, prime with a roller, feathering out the edges. Choose a nap thickness to match the surrounding wall texture (a 3/8-in. nap roller for smooth walls; 1/2-in. for textured).