Here are tips for cooking a good steak.
The tenderest cuts come from the short loin and rib primal. Good steaks to start out with are strip steaks, top sirloins, T-bones, Porterhouses, and ribeyes. Tenderloin cuts are pretty tender, but if you overcook them they can be dry.
Keep it simple. I like just salt and pepper, or a nice rub, but you can use anything that won't overpower the meat.
Rub the steak with a little olive oil and sprinkle on your seasoning.
Grilling, broiling, and pan roasting are classics, but feel free to use any dry heat method you want, such as sauteing. Also, at at least one point, you'll want to use enough heat to brown it. That makes all the difference.
Ever just sliced a steak as is and it turns out to be so tough you can't eat it? I admit that this has happened to me. But now I know how to keep this from happening. You know those lines on the meat? Slicing as thin as you can at a 45 degree angle will keep those short, which will mean tenderness. The only exceptions are tenderloin, which is so tender already, and cuts from the flank like skirt and flank which have a different grain structure.
Marinating can do a lot of things, but I'll tell you what it won't do. It won't tenderize. Commercial tenderizers use enzymes like papain, not acids! Okay, we got that over with. Now, when you pick a steak for marination, pick a steak with high surface to mass ratio, like inside skirt. Try to balance your marinade with salt, acidity, spicy, herby (if that's a word), and flavor. You're probably thinking, "What's the difference between a brine and a marinade?" One of the differences is that most marinades contain acids and not the huge amounts of salt like in a brine.
I hope you learned a lot about good steak.