Decide on a color scheme, theme and basic design for the room. For example, model the room after his favorite professional team or an activity he enjoys, such as surfing.
Paint the walls. Choose a solid color to allow for more freedom in updating the room again later or paint a bold pattern or design on the walls. For example, paint a beach setting with the sun setting over the water on one wall if she wants a beach theme. Stripes, geometric patterns, polka dots or faux finishes are other options.
Update the current furniture by upholstering the headboard with a funky fabric or painting other pieces. If your teen wants to include a lot of black, let him paint his furniture black instead of the walls.
Make your own wall decor. Paint images or put together collages of photos for an instant update that's easy to change if she changes her mind again.
Choose reversible bedding to give him more options for the look of the room. Alternatively, let him make his own duvet cover out of inexpensive sheets by using fabric adhesive if he doesn't know how to sew.
Accessorize the room with pillows, a lamp, artwork, trophies or your teen's other prized possessions. Glue beads, seashells or other decorative items onto picture frames or mirrors for a personal touch. Give her baskets, bins or plastic containers that complement her color scheme or theme to keep her things picked up and organized.