If you Google "veiled chameleon" in images you can get a good idea of the potential colors a veiled has. Most males are green and yellow, but some can have varying degrees of blue, orange, brown, etc. Some individuals are high-blue, or high-yellow, but on average green is the principle base color.
Adult, sexually-mature females will be a base color of green with yellow (sometimes called mustard) and blue spots.
Chameleons tend to get their adult colors more strongly at about 6 months of age or a little later. And these colors will continue to develop for up to another year, so if you have a small little guy he still has plenty of time to go.