I hate to sound like a negative nancy, but if your cham isn't very nice when you handle him, that's just his natural disposition.
Chameleons, especially veileds, don't tolerate handling very much, there are VERY rare cases where the chameleon MIGHT enjoy the handling, but these are solitary creatures by nature.
"playing" with him more will not make him friendlier, It will just stress him out and it could lead to health problems.
You could hand feed him, and this COULD possibly make him more comfortable with you so that won't hide as much, things like that, but i wouldn't handle him more then you ever need to (like when you need to move him to clean the cage, things like that)
Just respect his nature, and observe him for the amazing creature he is
