tell if it is done. unlike a meat thermometer or cutting into the steak, you're leaving the steak whole. that means that you won't have any delicious juices dripping out, and the steak will be that much better!
the only trick is, it takes a little bit of practice before you can tell how done a steak is just by pressing on it! but it's definitely worth learning.
just press lightly on the surface of the steak. be careful not to burn yourself!
if the steak feels soft, then it's still rare. you can press the steak before cooking it so that you have something to compare to. a rare steak won't be 