There are so many electrical problems that can cause your car’s clicking noise when you try to start it. Don’t play detective, digging under your car’s hood for clues (this can actually be dangerous if you’ve got a hybrid vehicle). Unless you know what you’re doing and have the right tools, you could wind up seriously harming your car, and yourself.
It’s better to get your car to a professional immediately. Take your car to a trustworthy, certified auto repair shop to help diagnose the problem and fix it quickly, before it develops into something more serious, dangerous—and costly.