If possible, find someone to help you lift the bike. If you have to lift it by yourself, there are procedures to help prevent you from injuring your back.
When picking up your bike, use leverage to avoid straining your back. If the bike has case guards (metal tubes mounted around the engine to protect the engine cases in a crash), grab the handlebars and roll the bike toward you on the case guards, using the bike’s momentum to get it upright. Bend your knees and use your legs, not your back, to lift the machine upright.
If the bike doesn’t have case guards, grasp the lower side of the handlebar (the side under the bike), turn the front wheel toward you, grasp some solid part of the frame, and work your knee under the seat. Then, use your legs to lift the bike. You might want to extend your side stand, in case you get the bike upright and it falls over in the opposite direction.
Don’t smoke anywhere near the fallen bike, since gas will most likely have dripped out. There may also be battery acid that has dripped out. This can burn holes in your riding gear and even your skin, as well as corrode metal parts on your bike. You’ll want to check the level of the fluid in your battery after a fall.
Once you’ve gotten the bike upright, check for other damage, too. Brake, clutch, and shift levers can get bent or broken in a fall. Riding a bike with a broken clutch or brake lever is difficult and dangerous. You may be in a situation where you have to ride away from your crash site with a broken or bent lever, but replace it as soon as possible.
Also check your wheels and tires after a crash. Make certain that a fender or chain guard isn’t rubbing on your tire. Make certain that your handlebars are firmly attached to your fork. If your handlebars break loose, you’re going to crash again. In the majority of all emergency situations, the only thing that will be hurt is your pride. Swallow it and count your blessings.
Once you have calmed down, reconstruct the events leading up to your crash. Chances are, in retrospect, you will remember ways you could have avoided the accident entirely. Remember these things the next time you ride, and you will greatly decrease your odds of ever crashing again.