Being Colorado native I've seen a couple of avalanches. I've never experienced one personally, though. It is quite an awesome experience to watch an avalanche, as long as you are far away. When a huge snow mass comes down a mountain side, a human being does not have much chance fighting against it. There are several things you can do to increase your chance of survival.
First of all, come to the mountains with a group of friends and watch out for each other. Bring some equipment with you, like probes, shovels, avalanche cords, etc. in case an avalanche happens and you have to look for victims. Do not try to show off by taking unnecessary risks.
If an avalanche starts right under your feet, which happens sometimes, try to jump over it. It might sound strange, but some people have done it. If you are in the middle of the slope and the avalanche is high above you, move to either side of the slope to get away from the center path. Grab a tree and try to hold onto it to prevent being dragged down with the snow.
When the oncoming snow mass knocks you off your feet and carries you down, try to 'swim' with the snow flow. Using swimming motion is said to help to keep a person on the surface and might prevent form getting buried deep.
After the avalanche stops, snow settles very fast and it will be hard to move if you get buried deeply. Take a deep breath to expand your chest to give you some room under the snow. If you can beat the snow in front of your face to give yourself as much breathing room as possible. Do not panic. Try to stay calm to preserve your energy. There are people looking for you. Obviously you have a higher chance of survival, if you are not buried too deep, but there have been many victims that died being buried only a couple of feet deep.
Shout for help to let your rescuers know about your location, although this might not know if there isn't anyone close. Your voice coming from under the snow will be very muffled and hard to hear, if at all noticeable. If you can see sunlight coming trough, you are fairly close to the surface and you can try to dig yourself out. Most of the time though there isn't enough room to move freely and your best bet is to wait for help.
You can call yourself lucky, if you ever survived an avalanche. There aren't many people that have done it by themselves. Unless someone finds you, your odds of survival are very slim.