Politically speaking? How about something like this:

1. He shouldn't have brought out Bill Clinton's accusers in the first place if he didn't want people to accuse him of hypocrisy. It was petty political gamesmanship that got him in this position to begin with.
2. He shouldn't have given such a half-hearted non-apology when he was called out; it was along the lines of "I'm sorry you were offended" not "I'm sorry, that was wrong and I learned from my mistakes since then", and then after his non-apology he tried to change the subject?
3. He shouldn't have his campaign advisor telling people that settling a lawsuit is equivalent to an admission of wrongdoing.
4. When faced with accusers, he should not say "they are lying" and "you are a disgusting human being," and sue the times for libel, but instead should say something that shows he isn't super insecure, like (just off the top of my head): "I believe these accusations are political in nature, and designed to defame me in advance of the election. I would argue that these accusations are not true, but of course I wouldn't want to undercut the importance of true victims of sexual assault coming forward in the future, so I will be happy to face my accusers in court and demonstrate my innocence. Until then, I would prefer to focus on the actual platform and issues on which I'm running."

In short: he should have acted like a potential president of the united states, not someone's weird uncle?