It’s not possible to actually pull the bar apart. But, when you try to do that while your bring the bar down and up it keeps your shoulder blades (scapulas) pinched together in the proper position. This way you actually use the muscles you want to train. Your chest, triceps, and shoulders will thank you.
Break the bar in half
Not only will you be pulling the bar apart, you will also be breaking it in half towards your feet. You should be trying to turn the bar into motorcycle handles. You should be trying to bend the bar into a cresent moon. This is going to activate your lats (back muscles), and allow you to keep your elbows from flaring outwards.
The hardest part will be breaking the bar in half on the way back up. Your elbows want to flare out. But we like healthy shoulders. So keep it tight!
Get your feet back and press through your heals
There are many different ways to bench press. But, by creating the most tension throughout your body and making a solid base to push from, you will be able to press more weight. Bring your feet back as far as you can so your heels are not touching the ground. Then try to press your heals to the ground. Most likely you wont be able to get them to the ground, that’s fine. By doing this you are creating tension and cementing yourself into the ground and bench.
Push yourself away from the bar
Push yourself away from the bar instead of pushing the bar away from you. When you think of performing the bench press this way something magical happens. You dig into the bench pad and get tight. Your head digs in, your shoulders stay locked back, and the bar drives up.
Set your breath
Use your diaphragm to breath while benching. Fill your stomach with air when the bar is at the top and brace against it. Lower the bar down and up and reset your breath again at the top.
Once you have this move down you can knock out a couple reps with one breath. For example if you are doing 10 reps set you breath for the first 3, the second 3, then 2, and the last 2.
If you breath into your chest all the bar bending, pulling apart, getting tight, all goes away because your chest will rise. All that tension is lost in the breath. Use your belly to breath and stay tight.