Ironically, the way to appear dumb is to just be ourselves. Normalfags look at socially awkward autists and immediately take us for fools, even though we often IQ mog them.
I made a thread recently which examined the etymology of the term "idiot" and its implications.
Idiot, in the Greek language, originally just meant "someone who appears unconcerned with the public interest, and who only seems to care about his own private interests."
In essence, it describes an autist who does not socially conform, and it acquired the connotation of low-intelligence over the years because of the normalfag conceit that loyalty to an ephemeral entity such as a city-state and social ingratiation generally is an indication of high intelligence.
Of course, this is belied by how normalfags are taken in by psychopaths (in Greek history, Alcibiades), who put on the trappings of social conformity, only to reveal themselves as the ultimate self-serving parasites.
And it might very well be the greatest weapon in the arsenal of autists themselves, not just psychopaths.
One obvious example that comes to mind is playing up our disabling, autistic symptoms in order to get NEETbux and live lavish lifestyles while NTgroids rot in wageslavery.
Another would be how Asian businessmen have historically taken advantage of how White businessmen look down on them, believing them to be stupid and incompetent. You can easily lure an arrogant enemy into an ambush. Take a look at this Asian NTgroid realizing his inferiority to his autistic kinsmen: