Tip for cooking a medium-rare steak:
The secret to the perfectly cooked steak is simply measuring the meat. When you know the height of your steak, it is much easier to calculate the cooking time.
Cook your steak on high heat for exactly 1 minute per centimeter on each side. A steak that is 3 centimeters high should be cooked for 3 minutes first on one side and then 3 minutes on the other side. Don't flip the meat constantly, but let it cook for three uninterrupted minutes. Every time you flip the meat, the pan's temperature drops, and it will be more difficult to gauge how much cooking time is left. You'll feel a bit uncertain the first few times, but with practice, you'll become much more confident in knowing when the meat is perfectly cooked.