Add the oil to the wok and heat on a medium to medium high hob on the stove until a few kernels added to the oil pop in a minute or so. The oil must be warm enough or else your popcorn will get too greasy, soggy and just nasty.
Once the oil is warm enough, open the lid and quickly (but safely**, you are dealing with hot oil here!), pour the rest of the corn kernels into the wok, then place the lid back on.
Reduce the heat slightly, and move the wok back and forth over the stove hob. Not too quickly (again, you are dealing with hot oil here!) and with short back and forth motions only-never up and down (again, you are dealing with hot oil here!). The kernels should begin to pop after ca. 1 minute, and fairly constantly.
Once the popping stops, open the wok lid (slowly-flying kernels may come at you with a vengeance) and immediately dump the popcorn into a bowl. Salt to taste and enjoy!
Recipe by Thanks For The Food at https://thanksforthefood.com/making-popcorn-in-a-wok/