Pocket squares and socks? I don't mean to sound flip, but what on earth?
Go-to-hell pants are those brightly colored trousers, sometimes embroidered with little sailboats, martini glasses, whales, etc., that you wear on the golf course or to the yacht club. Or the men's trousers from Lilly Pulitzer.
Rather than going to great lengths drafting my own postings, I've decided that it's easier to quote brief passages from the Official Preppy Handbook:
"In casual wear it is considered very spirited, very fun-loving to wear one offbeat, loud item -- usually the pants. Only one item of clothing may be this way, however. The total outfit must be traditional -- the usual uniform -- with the one exception. Tom Wolfe refers to pants in 'go-to-hell' colors; that's okay, but the pants must never be in a go-to-hell cut -- that remains strictly classic. The favored color is lime green, but go-to-hell pants come in other similar shocking colors. They may also have embroidered figures on them, but only appropriate figures... or a wild print -- but only an approved wild print. Being fun-loving should never be confused with being nonconformist. Occasionally a go-to-hell blazer may be worn with plain pants. There is not a go-to-hell shirt." p. 193.