[Stratmando]

An earlier mention that said you had to go to the end of the line on the GFI, It can be at the GFI or any other GFI protected boxes, still I wouldn't put on GFI.

[kitch428]

On your GFCI you should hook into the line side. If there are anymore outlets on that circuit and you hook into the load side of the GFCI. It WILL NOT work. The fan would have to be behind the last outlet.
Wiring: You can make the holes for your wire in a Horizontal line around the garage. BUT I wouldn't. Go vertical into the attic an back down. You can cut a 2- 6' X 12 ' hole up by the top head. One above the the GFCI and one above where you want to put the fan. Alot less to patch and only 2 holes to drill. And I would add a couple of more outlets. If thats the only one.
Have a Great Day Please let me know if this helped
RCallelectric- Jeff

I have this fan completely wired now. It's running like it should. Variable switch works good too.
As mentioned earlier, I wasn't sure if this was on a GFCI, but the opposite wall has the trip switch receptacle. When tested, it shuts down the hole garage except overhead lighting.
So, the receptacle I wired the fan to must be on the end of the run on the GFI, as there was only wire going into it, and nothing going out.
I connected my wire in the same manner as it was connected from house wiring.
Should I have done different? If so, why exactly?

[Stratmando]

Sounds good, A new load doesn't have to be End of the line, You could have load side go out of box in 4 different directions, and all would be Protected(Can be Star OR Daisey Chain, even both.