Once you put your steak in the pan, don't touch it! Otherwise it won't caramelize, brown, and develop a nice crust. That phenomenon is also known as the Maillard reaction — and you want to make sure to achieve it when you're cooking your steak. Once that crust is formed, you can flip the steak. If it's sticking to the pan, it means it's not ready yet, so wait a little while longer.