Dressing for Galatoires . . .
If you show up in jeans or khakis with a pullover and no coat, you are immediately pegged as a tourist.
Friday, indeed, is the best day (especially for the legal community) to visit Galatoires for lunch.
They begin seating downstairs at 11:30.
Although not mandatory until 5 PM, you should wear a coat. If part of the legal community (or even if not - the place is synonymous with class; although keep in mind that Stella took her sister Blanche to eat there in A Streetcar Named Desire, and the Kowalskis were not exactly classy people), wear a suit or a REALLY conservative, upscale odd coat/trousers.
Unless you want a table upstairs (and hardly anyone does), you are seated on a first-come, first-serve basis.
Between now and Mardi Gras, Fridays will be jam-packed with people.
You CANNOT make reservations for the first floor, and (I kid you not) it does not matter who you are or how well you are known. You get your seat after waiting in a line. True story: former U.S. Senator J. Bennett Johnson from Louisiana was in line to eat lunch one Friday. After being told by his staff where he might be, President Reagan called the restaurant and asked for him. One of the proprietors went outside, picked Johnson out of the line, and gave him the phone so that he could answer Reagan's questions. After the call, Johnson was politely escorted back to his place in line

This is no joke.
I apologize for "hijacking" the thread and bringing in Galatoires, but the restaurant DOES make for a sartorial adventure. You will undoubtedly see someone dressed (red pants/plaid jacket or light blue seersucker suit, both with pants way to high) that will make you say to yourself, "I am definitely in the South."
Regards,
Sam
P.S. General George Patton's niece was a regular at the restaurant until her death. I was told (by a pretty reliable source) that she dined at the restaurant EVERY evening.