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Sleeping on a plane can either be effortless or a true task.  Depending on how tired you are, how comfortable you are, and how long the flight is can affect the sleep you get on a plane.  So, here's a few tips to falling asleep quickly and easily:

• Invest in a travel pillow: comfortability is key to facilitate falling asleep and staying asleep.
• Sit in the window seat: if possible, try sitting in a window seat; this offers a wall to prop your head up against.
• Avoid caffeine: while waiting to board your flight, make sure to stay away from coffee shops and soda machines; the more tired your body is, the easier you will fall asleep
• Use the headrest cushions: on most newer planes, the headrest can be bent inward on both sides to enclose your head; this is helpful if you don't have a window seat, so you can lean your head on the cushsions.
• Ask for a pillow and blanket: flights can be a little colder than you're used to, so make sure to ask for a pillow and blanket to make it seem like you're in your own bed.
• Eat a meal before the flight: falling asleep is much harder when you're hungry, so if you don't eat prior to the flight then ask the flight attendant when the inflight meal is.
• Read a book: reading is a good way to make your eyes, and brain, sleepy.
• Headphones: if you're not a fan of white noise, and would prefer to fall asleep listening to music, getting headphones is a good way to block out external noise and keep yourself plugged in to your iPod or inflight radio/TV programming.