text:  Well, don't mess up, for starters. Obviously, a major misstep would define you and your campaign, I think particularly for Biden, because the image of him as not fit or mentally acute is a real one that the public shares, and Donald Trump is willing to concede this big deal for Trump as well. They're both the oldest men ever to run for president. I think beyond that, you don't want to seem, for lack of a better word, annoying.