How does this get wired?
New electric fan 1 blue 1 black wire
I guess the blue is hot? black is ground?

Relay
1 Terminal for fan etc..Blue wire?
2 " for ground , black wire from fan?
3 " for a switch (under or in dash)
4 " power source 12v relay or fuse panel?

I want to be able to turn it on/off at switch.
Thanks