I shouldn't have to say this...after all, it's obvious...but cartoonists shouldn't dress like the rest of humanity. Let everybody else have their wrinkleless, tapered shirts; a cartoonist should wear one-size-fits-all, boxy shirts that have to be gathered up like a bed sheet and stuffed into pants that are too big or too small. That's the way the Deity intended cartoonist men to dress, and any other way is blasphemy.
Of course there's something to be said for undersized clothing like the kind Harold Lloyd wears wears in the picture above. The clodhopper shoes are a nice touch. Come to think of it, the old lady, the kid, and the bum are dressed pretty well, too. They all dress like the stereotype of the kind of person they are, which is what cartoonists should do. That's what we can do to make the world more interesting.
It's not enough to have the nice threads (above). You have to learn how to strike the poses that set them off.
Naturally sneaky people (above) should wear the kind of clothes that look good on sneaky people. Dishonest people should always wear white gloves.
Middle age paunch (above) is a gift, which cartoonists should exploit. Wear the pants high, with a tight shirt and loose collar. Cultivate the disdainfull, irritable look that goes with them.
Padded shoulders (above) of course.
Throw out your shampoo. Wash your hair with bar soap (above) and comb it down the middle.
If you're a fairly mild person (above), then flaunt it. Wear clothes that emphasize it. Study hen-pecked husbands in old films and dress the way they dress.
If you're a big guy (above), then start dressing like a bully. Don't actually BE a bully...real bullies are evil...but there's nothing wrong with looking like one. People who look that way make the world more interesting.
I know what some of you are thinking: "I'm a big guy, but I don't have the personality required to look like I push people around." Well, you don't have to push anybody around. Here's (above) Eric Campbell, the guy who bullied Chaplin in so many of his best films. In real life Campbell was a nice guy who wouldn't think of hurting anyone. He simply geared up to look intimidating, and if you have the frame for it, that's what you should do.
Every cartoonist should find a funny stereotype that suits them, and dress that way.