Fire medic Jeff Rehman's job isn't just to save lives. His job is to save the lives of the people who are saving lives. It's because of this that he should be considered an authority on emergency situations. In this video that he published in 2012, Rehman shows you how to properly survive in a situation where you are choking and nobody is around to perform the Heimlich maneuver.
In just under two minutes, Rehman demonstrates, in his own home, the proper form of how to save yourself while choking. The technique, which was taught to him by an old boxing coach, has the victim go down to their knees and assume a push-up position. They throw their arms forward and thrust their torso into the ground. This creates a massive gust of wind from the lungs, hopefully expelling anything caught in their throat. Rehman mentions that no actual technique is 100% effective, so this isn't a surefire way to save yourself, rather the tool to give yourself the best chance of survival.