(I edited my previous response)
The section Leaving California that I referenced previously may help you.
"As evidenced by his actions" would include such things as obtaining a driver's license, obtaining vehicle license plates, and registering to vote in the new state. See Guidelines for Determining Residency on page 5 of the same reference for more examples.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
