That’s all there is to it. The incumbent need not do a thing — just get the hell out. And then we can all breathe again. According to Section 1 of the 20th Amendment to the U.S. Constitution:
The terms of the President and Vice President shall end at noon on the 20th day of January.
First the new President must take the following Oath or Affirmation*:
I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my Ability, preserve, protect and defend the Constitution of the United States.
*The option of an affirmation is for those who do not believe in paranormal phenomena. Some wonderful day we might even elect an Atheist.
P-A-R-T-Y at my house, starts one minute past noon on Wednesday 1/20. Wear a mask and have some bubbly!