Paint the walls with a muted or soft color that is in the pattern on the green sofa. This gives the room a unified look. If you don't want to use one of the existing colors in the pattern, beige or white shades are neutral tones that match almost any colors. Choose a beige or cream shade if the couch has a warm shade of green, such as sage. If it is a grass green, a white or off-white paint works well.
Add solid-colored pillows in the exact or complementary shade of green to the sofa if you want to detract from the pattern. If you want to accentuate the pattern, use solid-colored pillows in one of the accent colors in the design. This prevents the pillow from competing with the pattern in the sofa. Another option is to find pillows with a print that combines all the colors in the sofa. It is acceptable to mismatch patterns as long as the colors work well together.
Pick other fabrics with patterns to give the room balance. For instance, if the green couch has a floral pattern, choose an upholstered chair or drapes in a pinstriped pattern that complements the colors in the sofa.
Toss a soft afghan over one end of the sofa. Use an accent color in the afghan to draw attention to the pattern or a complementary shade of green to detract from the design.
Select furniture that has the same type of wood tone as the sofa if it has exposed wood. For instance, if it has light-colored oak carvings on the arms, don't use a mahogany coffee table. Using the same type of wood creates visual unity.