One thing he can do is quit touting that he is responsible for the vaxx. He doesn't need to back away from them, but stop bringing it up in every interview that he is responsible for them.
Then if he has to talk about it, he should strongly emphasize that he does not agree with any mandate, and remind people that he did support therapeutics & treatment.
From your lips to Trump’s ear, gub.
Very good advice, but it has to climb over the top of his tendency toward self-praise.
Sigh...