Our fearless non-President will "debate" tonight. 
So let's reset how badly he regularly gaffes / becomes unintelligible / flickers near off.
If none of this happens tonight... IF.. .He's a dynamic, vibrant speaker who doesn't mumble mode and doesn't absolutely trail off into nonsense at least several times...
I don't know what to tell you as to how.. there are several possibilities, including the one presented at the top of the cast... but IT... AIN'T... HIM.

00:19 The "Q" of the CIA speaking of mask-making from no later than 1992, when she was able to trick and spook a, well... spook. Former CIA director then President George H W Bush, no neophyte in such things, with a whole head disguise apparatus - neck, face, hair. 

1:50 Why relevant right now? My initial proposition (I spoiled it with my open here in the description).

4:58 A Precedent from The Memory Hole: That weird mechanism / apparatus / artificial organism on the same intellectually deficient candidate four years ago. Who remembers the mechanical shiny earthworms sticking out of his sleeve? It happened.

6:40 How he actually operates, gaffe example 1.

9:03 How he actually operates, gaffe example 2.

10:02 How he actually operates, gaffe example 3.

12:29 How he actually operates, gaffe example 4.

14:15 How he actually operates, gaffe example 5. 

Now go judge the "debate" with your eyes fully open.