Go to HireMarines.com. They have many jobs every day posted by residents and companies in North County that want to hire you on weekends and when off duty.
Here is an example: Serve Dippin' Dots ice cream, run cash registers, help maintain clean, organized sales stand, inventory control.
Beach Soccer Championships at Oceanside, CA Harbor Sat 5-14, 0800-1630 Sun 5-15, 0730-1800 (Can be 2shifts)
Venue is across I-5 from Main Gate Camp Pendleton on the beach Work by the beach, part inside small food service trailer, part outside Includes 1 meal Parking limited, come early, be dropped off or walk in $13 hr.