I can provide you with a quick easy way to perform it.
Put your closed fist, pinky side down, across the bellybutton, then roll your hand up, so the thumb side of the fist is mid-abdomen. From behind, of course, do quick upward thrusts until the object expels. Anyone that has the Heimlich done should be seen by an ER just to be sure nothing is damaged.
ONLY do this if one can not speak, breath or cough. Otherwise, just watch them closely.
If they should pass out, while they are on the floor---basically perform CPR--except when you do the breaths, look for the object each time you pause to give breaths. The hope is that the chest compressions bring the object up where it can be reached, or the breaths move it enough that air gets to the lungs.
If strong enough and home alone, you can perform the Heimlich on yourself. First, from a landline, dial 911 and sit the phone on the counter. Pick up a hardback book and do thrusts on your mid-abdomen as hard as you can while you walk to the front door and open it. If you pass out (and you will if you don't dislodge the object) you need the police to find you immediately at the open door so they can treat you.
I've taught CPR for years--this is a very simplified version of how to do it.
CPR is simply using chest compressions with two hands in the center of the sternum. 30 compressions and 2 breaths (even without breaths can help)
Someone's chances of survival improve by 40% if CPR is started early. Chances of survival go up to nearly 70% if there is an AED used.