In my research recently amongst the many ordinances of San Francisco, I did not find what I was looking for, but I did happen to come across something far more exciting. It appears that Article 17.1 of the San Francisco Municipal Code makes fortunetelling permits pretty widely available to anybody who applies for one (and can pay the license fee). Section 1305 of that article says that the Chief of Police "shall grant the permit" unless the applicant has been convicted of a felony relating to fraud in the past seven years, or unless other fairly narrow exceptions apply, none of which, I noted, would apply to me.
This permit enables its holder to legally practice fortunetelling within the City and County of San Francisco, said "fortunetelling" being defined very expansively to include:
the telling of fortunes [really?], forecasting of futures, or reading the past, by means of any occult, psychic power, faculty, force, clairvoyance, cartomancy, psychometry, phrenology, spirits, tea leaves, tarot cards, scrying, coins, sticks, dice, sand, coffee grounds [coffee grounds?], crystal gazing or other such reading, or through mediumship, seership, prophecy, augury, astrology, palmistry, necromancy, mindreading, telepathy or other craft, art, science, talisman, charm, potion, magnetism, magnetized article or substance, or by any such similar thing or act. It shall also include effecting spells, charms, or incantations, or placing, or removing curses or advising the taking or administering of what are commonly called love powders or potions in order, for example, to get or recover property, stop bad luck, give good luck, put bad luck on a person or animal, stop or injure the business or health of a person or shorten a person's life, obtain success in business, enterprise, speculation and games of chance, win the affection of a person, make one person marry or divorce another, induce a person to make or alter a will, tell where money or other property is hidden, make a person to dispose of property in favor of another, or other such similar activity.
S.F. Muni. Code § 1302(a). Even better is 1302(b):
Fortunetelling shall also include pretending to perform these actions.
So, if I go down to the San Francisco police department and fill out a form telling them that I want a permit to tell the future through necromancy (talking to the spirits of the dead), they'll give me one. In fact, they have to give me one. In fact, I can get a permit to pretend to be a necromancer. "Did someone call for a Certified Necromancy Pretender? Here's my card."
The point, of course, is to make people register, or more likely to bust them for not registering when they catch somebody engaged in fortunetelling. But the ordinance also states that one of the purposes of the legislation is to "foster a positive business environment for legitimate practitioners within this industry." S.F. Muni. Code § 1300. Music to the ears of legitimate phrenologists everywhere.
I also learned that (under a different part of the Code) you can apply for a permit to own a squirrel monkey, but that is much harder to get.