You are in India, whereabouts? I have been to a few holis. There tends to be a lot of coloured water thrown around as well, even buckets full, so watch for that, also make sure you have nothing that can be stolen from you in case you take a bucket of water to the face (I lost a compact camera that way, setup pickpocketing by a bunch of kids). Just check your surroundings some groups/places/cities are much more intense than others, some are more relaxing. Lots of people stick to the rooftops as well. Basically if you are really afraid to lose or damage it, prob best to leave that gear in the room. Enjoy! I am heading back to India in a few weeks but sadly will miss Holi this time. Watch out for the special green lassis and sweets everywhere too, they pack a punch
Also from what I remember black and red powders are the worst and take many days to come off your skin...