What You're Doing Wrong: For this classic lift, many guys make the mistake of having their elbows out wide or, even worse, behind the bar. Another crucial mistake that will cost you from hitting your next personal record is your bar path. As the weight increases, you might see yourself doing a diagonal bar path instead of pushing up vertically.
How To Do It: Start with tension on the bar by bringing elbows slightly in front of the bar at resting position. The next step is very important and is why your head is the most important part of the strict/military press. Push the bar up while moving your head slightly back and out of the barbell path. Once the bar clears your head, press through with your shoulders while simultaneously pushing your head through the window created by your arms. It should be a quick, violent movement, but pushing your head through will allow your body to push the bar all the way up, especially as the weight gets heavier.