In general terms, it is very difficult to become a licensed architect without first obtaining a NAAB accredited degree in architecture (www.naab.org). However, very few states will allow an individual to become registered with either a preprofessional degree in architecture or a high school diploma, but the experience required would be increased.
As it turns out, California is one of those states. With only a high school diploma, a candidate would need 8 years of acceptable experience. For more details, contact the state board in California or the following:
While it is possible for you to pursue licensure without any additional schooling in California, I would NOT recommend it. First, you will find it extremely difficult to secure an intern position with no background in architecture. Next, as most states and NCARB require a NAAB degree for licensure, you will be limited to practice only in California.
I recognize that you wish to avoid school, but architecture is a very technical field. As such, you have much to learn both in the classroom and working within a firm.