There is a mile high club. And you suddenly know what that means.
The Suit does come off.
Stay away from blond district attorneys. And DEA agents with a strange taste in art.
Fund modern art (holograms, etc.) - it might save your sorry a$$ sometime. (Especially when your competitor makes a point of educating your love interest in it.)
You really don't want to know what it's like on New Krypton. Honestly.
Superman is married to Ultrawoman.
You want to found a Hate Lana Lang Club.
Jimmy is always Jimmy - no matter the new look after S1.
Don't worry too much about finding the one and only right wedding gown - you might not need it, after all.
You learn a few new curses. (Great shades of Elvis! What in the Sam Hill...)
You could teach Miranda a lesson on affecting Superman - try pasta instead.
Stay away from things (and location) with a strange smell. (Metropolis Sewage Reclamation Facility, Eau de Sweat Socks, Space Rats, kryptonite gas, dumpsters behind certain bars, etc.)
John Doe is a darn nice guy, Lois Lane is galactically stupid and Bill Church is a law-abiding citizen. Oh, and don't forget, Mindy Church is positively harmless.
Beware people travelling through time with long-dead writers.