How Do You Add Gunshot Sounds and Muzzle Flash Upon Gunshot?

Hey, how do add gun shot sounds and muzzle flashes upon firing a gunshot?
I already have the gunshot action, but no effects when firing.
How do I add them? (by the way, i’m on an iMac)

For the gunshot sound: drag the audio clip you want to use onto your gun and use audio.Play();. For the muzzle flash 1