Getting Cross grill marks on your steak is pretty easy.
You need a good hot pan. We like a 12 inch cast iron grill pan. The only thing a good steak needs is salt and pepper, so coat both sides and make sure the steaks are out of the fridge for a while so that they are not so cold (30-60 minutes).
Once the pan is really hot lie your steaks down and do not touch it for 4-5 minutes.
At that point give your steaks a quarter turn and cook for another 2-3 minutes. That will give you the cross marks. Then just cook the other side for around 4 minutes and let them rest for 10-15 minutes under some foil.