Potty training

Ok. So my son is almost 2 1/2 and my hubby and I are going to have our next baby in a few months. So we’re determined to get our son out of diapers. We are officially starting potty training today. But the one problem we’re facing is he doesn’t want to be on his potty naked. He’s fine while wearing his diaper or pants. But when we try to take off his clothes to sit on the potty he freaks out and tries to run off. Does anyone have any recommendations or tips on how to potty train a boy and how to get him to sit naked on the potty? Thank you