Bench Press Form Check

You can't make a topic with the words form check and not post a video....

what a tease. 

also, those two things aren't the only components of a bench press. 

Well your back isn't really arched, you're not tight--back or legs, you're not locking out, and your head's lifting off the bench. 

It looks like you use shoulder wide grip or something. Maybe your doing close grip bench press but I think it's easier with a grip that makes forearms straight down to the floor.

Your legs keep moving left and right, your head keeps moving around and your breathing seems erratic.

Here are some good pointers from Jim Wendler (from his 5/3/1 programme):

␣   Your shoulder blades must be pushed back, and your chest must be spread throughout the bench press. If you’re benching without the aid of a bench shirt, most of the bar weight (and your bodyweight) should be supported by your upper back. This will help keep the bar from touching too low. It will ensure that you don’t lose your tightness, and that you’ll be pressing from a strong bottom position.
␣   Your lower back should be arched and kept that way. This does not mean you lift your butt off the bench.
␣   Again, do NOT lift your butt off the bench. This bears repeating.
␣   Foot placement is up to you, but make sure they’re in a solid and strong position. I like to place my feet back slightly toward the head of the bench, and I assume a stance that’s narrow enough to allow my legs to squeeze the bench. As I press up, I drive my heels into the ground and squeeze my legs, picturing all the energy from my legs and hips driving into the bar. This is “leg drive.” Think about squatting the weight up.
␣   Grip width is also up to you. Over the years, I’ve found that a narrow grip is a little healthier in the long run than a wider grip. My grip is around 18” between index fingers. This may limit my weights in the short term, but it’ll ensure that I won’t have any pec or shoulder problems in the long run. It’s better to press today and tomorrow than just to press today.
␣   As soon as the bar is in your hands, make sure your lower and upper back are arched, your feet are firmly on the floor, and your hands are wrapped tightly around the bar.
␣   I like to take a large breath and force it into my diaphragm before lifting the bar off. This helps me feel stronger and more stable when I get the bar. A strong and easy lift-off is a great way to improve your lift and your mental state. Again, don’t “wimp” the bar off the rack.
␣   Don’t use a lift-off partner when you train. Use this only for maximal attempts.
␣   I usually hold my breath for the first 2-3 reps of every set. This is hard to do, but it ensures good technique and you won’t lose tightness.