What are the best techniques for applying gloss paint to walls for a smooth and professional finish?

To achieve a smooth and professional finish when applying gloss paint to walls, it is important to properly prepare the surface by cleaning and sanding it. Use a high-quality brush or roller to apply the paint in thin, even coats, working in small sections to avoid drips and streaks. Allow each coat to dry completely before applying the next one. Sand lightly between coats for a smooth finish, and consider using a paint conditioner to improve flow and reduce brush marks.