Mmm, steak.
OK, first things first: the basic process is to sear both sides, then roast to desired doneness.
If you suspect your cut of meat may turn out tough, or you want to add flavors, use a marinade of red wine, vinegar, and your preferred spices.
Next, get a broken-in cast iron skillet, put it on your stove or grill, and turn it up to 11. While it's heating up, set your oven to 300 or so. Make sure your skillet does not have a PTFE lining, or else you won't get a proper crust.
When the skillet is about to melt, put the steak in the center of it. Yes it'll smoke like crazy; don't worry about it. Wait 2 minutes, then flip it over and sear the other side for another 2 minutes.
At this point, if your steak is less than 1" thick, it's probably done. If your steak is thicker or you prefer it more done, then put the pan in the oven and continue roasting until the internal temperature is just above 120°F (after 10 minutes of resting, it'll come up to 130°F which is about medium.)
If you need toppings on your steak, some favorites are browned shallots and butter with raw onion blended into it.