Bay windows can easily be the main focal point in any room of your house. Help your window looks its best with a fresh coat of paint on its decorative trim and within the arch of the window. Choose an interior paint that's at least contractor-grade in your desired color. Moisture tends to puddle in bay windows if they're not properly weatherproofed, so clear the area of any rot or mildew before beginning your project.
Clear the window and surrounding trim area of all dirt and debris. Wipe down the surface with a damp rag, removing any dust. Use a glass cleaner to remove more dust or mildew.
Level your painting surface or smooth any rough edges, using a fine-grit sandpaper. If needed, use a wood filler or caulk to close any gaps or cover any nail holes. Once the filler or caulk has dried, sand again and remove excess with a warm, damp rag.
Place painter's tape in areas you want to protect.
Apply your paint to your window, using an angled brush. The size of the brush depends depend on the width of the trim surrounding your bay window. Generally, your angled brush should be no wider than 2 inches.
Paint the trim surrounding the window. Paint vertically, never side to side. If your window trim is wood, follow the grain. Start from the center of your trim and work your way out to the edges. Allow the paint to dry fully and remove the painter's tape.
Avoid applying too much pressure around the trim where you applied your painter's tape. This will cause the paint to bleed and your trim lines will not be straight and even.