barbell overhead press
The bar is positioned directly below the chin but above the collar bone. The elbows are directly below the writs and barbell. Squeeze the abs and glutes to prevent the lower back from overextending while pressing.
Relax the knees, squeeze the glutes and begin pressing the weight over head. Move the head back slightly so the bar is able to travel in a straight line. If the bar travels even slightly out in front of the body, strength will be lost and more stress will be put on the lower back.
After the bar clears the face and continues to travel upward, gradually move the head back to it's neutral position.
As the elbows lock out, the bar will finish directly above the ears. Prepare to bring the weight back down to it's starting position by slowly bending the elbows. The head should move slightly back just as it did on the way up to help the bar travel in a straight line.