(1) Make sure you're connected to XOHM.
(2) Visit any webpage, and you will be taken to an activation page.
(3) Login or create an account if you don't have an account.
(4) Enter credit card and pick service type (daily, monthly).
(5) Done.
(6) Now you can surf the web!

As for the where part of your question, I'd (we'd) need a map of sorts upon which to place our dots.