Getting to International Airport for Travel to USA
Clothes
Wear comfortable clothing for the long flight, and be sure to wear your shoes. You can remove your shoes in flight (some airlines give in-flight shoes, or you can relax in your socks). Chappals are fine, but you might feel cold at an intermediate place like London.

Arriving at the Airport
International airports are usually divided into two sections: top floor for departures and ground floor for arrivals. Departures might be divided into different sections according to the airline. Check for your airline's terminal. As you drive into the airport, you will also see a big board that displays airline terminals. Your travel agent or airline can also inform you of the terminal.

If you didn't obtain foreign exchange before arriving, you can collect around $50 to $100 at the airport. Make sure some of that money is in $1 denominations. You may also want to keep around Rs.1,000 in Indian currency for miscellaneous expenses and unforeseen needs.

Once at the airport, you will see many signs and directions. If you are not clear about something, feel free to ask for help from the airport staff or airline personnel.

Escalators
Many international airports have escalators, also called moving staircases. If you have not used them in past, they may initially look scary. However, if you observe others riding them and if you follow the proper steps, they are not complicated. While approaching the escalator, you should make sure that your feet are only on one step and not over two steps. When you are approaching the end of the escalator, keep one foot lifted and be prepared to walk. When the escalator ends, step down with your lifted foot and start walking normally. If you have any trouble or encounter unexpected hazard, there is usually an emergency stop button that security staff or others can press to stop the escalator. 

Often, there are also plain staircases available as an alternative. However, some airports have no such alternative. 

Seat Allocation
Seat allocation varies with different airlines, and depending on the duration of the flight, it may vary with different routes. There are no uniform criteria for seat allocation.

It may be possible to reserve seats at the airline website. Seat allocation is usually made at the check-in counter. Some airlines may allow you to reserve a particular seat at the time of booking. If you have a seating preference, especially if traveling with small children or infants, or based on special medical needs, you should speak to the travel agent or the airline about them as early as possible. If you can't reserve a particular seat in advance, you are recommended to arrive at the airport sooner than the normal reporting time.