Initial Seasoning of Carbon Steel Woks: 

Your steel wok must be seasoned before using the first time. Remove preservative oil by scrubbing wok in hot, soapy water. Dry thoroughly. Apply a light coat of cooking oil to the entire inside surface with a paper towel. Heat your wok until bottom turns golden brown. This seasoning seals the pores of the metal and keeps food from sticking.

Care of Carbon Steel Woks:

Wash your wok after each use in hot, soapy water. Do not use harsh abrasives or scouring pads as they can harm the protective seasoning. Dry thoroughly. Apply a light coat of cooking oil to the inside surface with a paper towel. Place the wok over medium heat for 15-30 seconds. Remove from heat and allow to cool. Wipe off excess oil before storage.

Discoloration: 

Your steel wok will discolor and darken with use. This is a sign of a well-seasoned utensil.

Rust:

If you leave your wok in a damp place, it will develop rust.  Luckily, it is a solid piece of metal.  You can scrub the rust out with a kitchen scrubbing sponge or steel wool.  Re-season following the instructions above.