Then put signs all along the Mexican-U.S. that show a little arrow pointing to California with the caption that reads (in Spanish, of course) "Thataway for jobs and free health care and housing."
As to how California would fare if kicked out of the American union -- the regime could appeal to the International Monetary Fund for help. I can't wait to see the kind of austerity measures the IMF would impose on California in exchange for keeping the new country afloat. You may trust the first loan condition would be scaling back on bloated welfare programs.
Then California could borrow from the World Bank to build a wall all along their border and Mexico.