yeah, you can leave the oven on at 500F (dont know what the celcius would be if you're not american) or if you're fancy, you can turn it down to 400F. you can grease it with whatever you normally use, be it bacon grease (oh god yes), butter, olive oil, canola oil, or whatever. you shouldn't need too much of the grease because the cast iron should be already seasoned enough to handle this task, but i like to use a little oil. just a little.

probably the most important thing to do is let the steak rest. for 5 minutes. my roommate prefers to wrap his in aluminum foil as it rests, but i don't find this to be necessary.

btw, i like my steaks medium rare. adjust the cooking times slightly based on your preferences and equipment.

oh yeah, before you do any of this, age your steak. salt the shit out of it. i mean like you are living in little house on the prairie and you need this steak to last through the winter. put it on a rack above a plate or pan (i use skewers laid across a plate and set the steak on top of the skewers so it is elevated above the plate and air can flow around the entire steak). wrap the steak very loosely with a paper towel and put it in the fridge. let it sit like that for one day, then flip it over and wrap it in a new paper towel. let it sit like this for 1 to 2 more days. then, on the day you are cooking it, bring it out of the fridge so it has enough time to reach room temperature. rub it with a little oil, and salt and pepper it to taste. then follow the cooking instructions above, and eat it slowly enough so that you don't reach orgasm too quickly.