Spinnerbaits are one of the easiest baits to use and are normally a fish magnet.
As mentioned by davey buoy, you need to experiment with different colours and weights, but you can also change blade styles to get different depths. A Colorado blade will keep a bait up high, while a Willowleaf will allow it to run at a deeper depth.
If fish are hitting your bait but not getting hooked, you can add a stinger hook to the back of the main hook.
I always run 1 or 2 rubber worms on my baits, but that's just me, but is something you could try also.
If straight retrieves aren't working, try banging and bouncing your bait off rocks and other structures, or get it down deep into the weeds and work it through them at different speeds.
Most importantly though, you need to be fishing where the fish are.
It's tough to work a spinner bait wrong, so if your not catching, just keep changing your tactics until you figure out a pattern and then you'll do just fine.