Basically, remove the beeswax layer, then rub a layer of oil on the pan and heat it until it fully smokes off. You can do it on a burner or in the oven at 450F. You'll do that a maybe 3-5 times on a new pan, up to you. They tell you not to do carbon steel in the oven because of the material of the handle, but I've done it before and it worked out fine. I generally just use the stove top because it's easier.

You clean the pan with soap and water as you would any other pan, and then towel dry since you don't want rust forming on the metal. You'll need to re-season it every so often depending on how much use the pan gets, but that's usually only every couple years.

[1] https://www.seriouseats.com/how-to-season-carbon-steel-pans