For the most part the color is determined by genetics. You can ensure your dragon looks and feels his best by providing good nutrition, proper habitat with correct UVB, lighting, and basking area, and a sanitary environment.
As your dragon regulates his body temperature he will be different shades throughout the day
Your beardie looks quite young. Colouring will come out more with age, too. I didn't even know Mort would have any orange in her when I got her at 5 months old.