If you have a very low IQ
But are physically OK, play sports and/or enlist (US-centric).
Another bonus of enlisting: basic skills will be drilled into so thoroughly they will be fully into your System I allowing you extra executive function (thereby causing you to punch above your weight in terms of intelligence). Although, there is some ethical risk involved.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.