Are you staying at Gage Residences? I'm assuming you're coming to attend an on-campus workshop and that's typically where UBC Housing puts up visitors. If so, the bus is an option as Gage is only about a 2-3 minute walk from the main bus terminal.

If you're coming for a week, though, you'll probably have a fair bit of luggage and taking 3 buses is a bit too much. A cab will run you about $25-$27 - I work on campus and frequently head directly there after flying in from a business trip and it's never cost much.

If you have any questions about what to do/where to eat/shop on campus I'd be happy to answer them. Definitely get in downtown for as many visits as you can though, and don't forget to explore Kitsilano too