Use vinyl window clings to spice up the bay doors during the holiday season or use them year-round if it's a bay door of a child’s playroom. Find window cling leaves or pumpkins for use in the fall seasons or use window clings that depict cartoons for a kid's room. Peel the backing away and stick them directly to the windows and door.
Take advantage of the added depth that a bay door has by displaying three-dimensional objects along the sides of the door, below the window areas. Place small tables with decorative accessories on them, put a coat rack on one side and an umbrella stand on the other, or display tall sculptures.
Install shelves above the bay door that follow the contour of the feature. Use floating shelves to avoid the need for brackets. Fill the shelves with a collection of something, from small framed pictures to colorful ceramic vases.
Cover the windows on and surrounding the bay door with decorative film, which can add privacy while still allowing light through. Cut the film to the size of the window, peel the backing away and use the edge of a credit card to smooth any air bubbles away.
Install a curtain over the bay door area to restore a flat appearance to the wall if desired. The curtain also provides privacy and blocks the light. Use curtains that match other ones in the room for continuity.
Paint an inspirational quote right above the bay door to greet people as they leave the building. Use letter stencils for guidance if you aren’t comfortable painting free-hand.