When something is embellished or made more beautiful, it's decorated, like the elaborately decorated cookies you made your parents for their anniversary.
Besides things that are ornamented or adorned with decorations, you can also use this adjective for people who are honored, particularly soldiers who have served heroically. A decorated war veteran has received medals, awards, and honors from the military. Decorated soldiers often wear their medals on their uniforms. The Latin root of decorated is decus, "an ornament."