If you're using an electric stove, turn it on and set it to medium-high heat for 2 minutes.
Add popcorn kernels, oil, and butter to a cold pot.
If you're using a gas stove, turn it on medium-high heat.
Place the pot on the stovetop, and stir every 5 seconds. The goal is to evenly disperse heat throughout all kernels.
When the first kernel pops, stir vigorously until 4-5 more kernels pop, then close with a lid.
Slightly shake the pot while the kernels are popping, keeping it ontop of the heat source.
When only one kernel pops every 3 seconds, remove pot from the heat and open the lid to release steam.
Transfer popcorn to a bowl, salt, and serve.