As you press a bar overhead, there's often a tendency to point your nose up to the sky to avoid smashing the bar into your chin. This is a natural reaction and makes practical sense. The last thing you want to do is destroy all that expensive dental work that kept you in braces during your teen years.
The problem? This technique also forces you to loop the bar forward, taking it out of the most ideal plane of motion, which is directly above the center of your feet. This makes you weaker.
The Solution: Make a Double Chin
Instead of looking up, retract your entire head directly back, as if you were making a double chin. The bar should pass directly in front of your face on its way up. This will keep the bar path centered, balanced, and along the strongest possible path.