"You look so ..." You nod encouragingly, complimentary adjectives abound in your exhausted mind. " Tired."

We've all heard it, after a long flight or a late night on deadline, up with your kids or up with your thoughts. No brightly colored shirt or zealousness can hide it. You are tired. And it shows. "Turns out when grandma said get your beauty sleep, she may have been right," says Cheryl Myers, RN, integrative medicine and natural beauty expert. When you get into stage three or four sleep your body makes human growth hormone, which is often referred to as the body's natural antiaging hormone, says Myers. "When you go to sleep skin is repaired and replenished and made ready for another day. Every time you take an hour away from healthy sleep you are making that much less growth hormone and it is going to show up on your face." So how do you know how much sleep you need and how to reach stages three and four? Myers offers some simple tips for getting your beauty rest.

First thing's first: find out your personal sleep needs. Most people need between 7 and 9 hours, says Myers, but there are exceptions. "I knew an Aerospace medicine physician, smart and energetic. He only needed four hours of sleep a night and was healthy, vigorous, looked good with high HDL (good) cholesterol levels, and low LDL (bad) cholesterol levels. He had two daughters one slept around nine hours a night and the other slept four." How do you know what's right for you? Choose a week to go to sleep when you feel tired and let yourself wake up naturally (if a full week isn't possible, you can probably get a sense over the course of a long weekend). Adjust your schedule so you can get this much sleep most nights; then make sure you reach stages three and four by following these tips.

1. Sleep in a completely dark room with no digital alarm clock or TV. Even small amounts of light can prevent you from reaching this stage. Also make sure your shades block out all light.

2. If you get up a night, try to make it to bathroom without turning lights on

3. Keep the temperature cool. You don't want to be chilled but cooler temps tend to promote deeper sleep.

4. Take a warm shower before bed, or do some gentle yoga to relax your muscles.

5. Don’t do intense exercise after 6 pm.

6. Have a small protein snack (about 100 calories) half hour to an hour before bedtime.

7. Don’t take prescription sleeping pills, which will limit your sleep to stage one and stage two, maybe with a dip into stage three. These pills prevent you from entering into natural, deep, healthy sleep. After a period of time, you will experience a stage four deficit.