In his Farewell Address, Trump should talk about the successes of the country, especially under his leadership, and how even though some things did not work out, the country in total is better. He should go out with a bang, make some jokes, but overall say farewell. He will most likely address the wall (and if he has built it) and how it helped/ didn't.) He should tell the country how they can continue helping after he has left the presidency, and encourage people to vote.