If you are choking and there is no one nearby, you can give yourself pushes to your stomach in two ways.
Make a fist with one hand, pressing it from the thumb side to the middle of the abdomen, just above the navel and well below the end of the sternum. Cover your fist with the palm of your other hand and make a sharp push upward. Or (2) lean forward and lean your stomach against a hard object, such as the back of a chair, a railing, or a sink, and press it inward. Do not lean on things with sharp edges or corners, as this may cause injury.