Short answer: You probably can’t, which is another reason friends shouldn’t let friends use GoDaddy.
At least, I’ve confirmed that this is the case with GoDaddy’s turnkey “managed” WordPress hosting service. If you’re a developer unlucky enough to have to work within this hosting plan, and if you’re trying to modify your template files via FTP, you may notice that your changes aren’t taking effect right away. Apparently to reduce the load on their servers, GoDaddy has added a caching feature which cannot be disabled. (It’s probably implemented at the server level, not as a WordPress plugin at all.)
The quickest way to force your page to load fresh is to add an unnecessary variable to the end of your URL each time you reload the page, like so:
Just increment the junk variable each time you need to reload the page: junk=2, junk=3, etc.
Alternatively, if you login to the WordPress dashboard, you’ll find a Flush Cache button at the very top of the screen, just to the left of GoDaddy Settings. If the mandatory caching is too much of a headache, contact GoDaddy and ask them to switch you over to a traditional hosting plan and install WordPress yourself. Or switch to a better web host.