- 1). Choose the pattern you would like to see around the window. Look at wallpaper borders and china patterns for inspiration. Practice painting the pattern on a piece of scrap paper, illustration board or scrap board.
- 2). Draw an outline around the window to show the perimeter of the trim. This outline should be spaced 3 inches away from the window's edge, or as far away as is your preference. Use a ruler for the straight edges.
- 3). Draw the pattern lightly with a piece of chalk or a pencil, the outermost edge touching the line you drew in the previous step.
- 4). Paint the pattern you drew in the previous step. Use a color wheel to pick the colors if you are using multiple colors. The colors you use in your pattern will usually look best if they have a relationship on the color wheel (they are found opposite one another on the color wheel, or are found side by side on the color wheel), or if they match colors found elsewhere in the room. Use an acrylic paintbrush. For larger areas of color, use a flat paintbrush, and for smaller areas, use a detail brush. Blend colors together using a dry brush.
- 5). Allow the paint to dry. Touch up the paint when the pattern is dry, then if no touch-up is necessary, erase any visible pencil or chalk marks still on the wall.
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