Hooping and centering designs and logos

Hello!

New member here hoping to find some tips/tricks/advice for a problem I'm encountering more and more. I have two 15-needle machines. I've embroidered for over five years, and my little hobby is slowly turning into a small business. I'm familiar with most of the processes, stabilizers, threads, etc. The one thing that is driving me crazy lately is centering logos on either chest! I have the marking templates, measuring mat, and I've used masking tape, but I have had more failures than successes. What is the secret to putting a logo on a polo shirt or jacket and having it come out level? I am so frustrated, it's making me want to quit, but I don't want to do that either. Please share your knowledge with me or suggest videos I can watch, anything you have! Is there a table top level light or a template tool that works better? I'm at a loss.

Thank you so much!!!