The Problem - Letting the slingshot change your positioning
A common issue I see when people first throw on a slingshot is letting the slingshot determine your positioning when you press. Lifters often let the material pull their elbows in too much or change their touch point on the chest to accommodate the slingshot material. This is not what you want to see, it is a result of not wanting to let the material stretch as it's supposed to
The Fix - Make the material form to you, don't change for the material
The first thing I tell lifters when they throw on the slingshot for the first time is simply, "don't change a thing". Get into your same set up, grab the bar the same, and keep your bench groove the same. Let the material form to you. The material doesn't dictate where or how you bench the bar. Let the material stretch as it will and keep everything the same.
This will prevent you from making some of the common mistakes seen such as over-tucking the elbows. The more the material stretches the bigger boost you will get in the bottom of the bench. This is ideal, don't try to resist the stretch by keeping your elbows tucked. The slingshot should be positioned right over the elbows, I even wear my slingshot slightly over the elbows for an even larger stretch boost
Remember to let the material form to you, not the other way around, This will prevent most faults. For more info on how to use the slingshot for benching, please feel free to email me at email@example.com