One suit( Black or dark blue preffered). If you are going to a business school get two because you will be using it a lot more.
Ties (1-2). Get good quality ones, do not skimp on them. Ties and shoes are the most important piece of an attire
Formal shirts and trousers (number of your choice, dress to classes is more casual)
Casuals
Regular blue Jeans (number of your choice, but at least 2 is recommended)
Casual T-shirts/shirts (6+)
Shorts (for outdoor, indoor, sports use)(number of your choice)
T-shirts and shorts are common in the spring and summer
Get shorts that are on the longer side
Also try to make sure your shirts are of the type that do not require pressing/ironing
Footwear
Sneakers
Formal shoe
Sandals
Bathroom slippers. Old Navy in the US has good cheap slippers, you can get your next pair in the US there.
Underwear
At least 15 sets of underwear. It reduces the number of laundry cycles. Coin operated laundry is mostly used through the US and people wait until they have a load or two of dirty clothes before going to do the laundry.
Socks , preferably cotton. Also get socks that match your formal pants.
Misc
Towel
leather belts (2+) (one formal leather belt and others as you please)
Atleast one traditional Indian dress
Good leather wallet, preferrably one which can hold lots of cards