What to attach to your California state return will be listed in your filing instructions that print put with your return.
"Other than Schedule A (Form 1040) or Schedule B (Form 1040), did
you attach any federal forms or schedules to your federal Form 1040?
If No, do not attach a copy of your federal Form 1040 return to
Form 540.
If Yes, attach a copy of your federal Form 1040 return and all
supporting federal forms and schedules to Form 540.
Exception: If you did not itemize deductions on your federal tax return
but will itemize deductions on your California tax return, complete and
attach a copy of the federal Schedule A (Form 1040) to Form 540.
Attach all the Form(s) W-2 and W-2G you received to the lower
front of your tax return. Also, attach any Forms(s) 1099, 592-B, and 593
showing California income tax withheld."
Ca=540 Instructions (pg. 19): https://www.ftb.ca.gov/forms/2017/17_540bk.pdf
