This involves you being able to ignore your gag reflex
1. Pour some minty fresh Listermint into a small cup, just enough that you can dip your right index finger (if you are right handed) into it. This disinfects (somewhat, assuming you also washed your hands first) and lubricates your finger.
2. Where you feel the rice/food is stuck, put your finger there at the very back and top of your throat (it should be a soft palate, not the hard palate of your mouth...