12 useful titbits from usertesting.com. Many of these apply to in-person testing too.
usertesting.com have offered me a free trial code to pass to friends, so if you work at the University of Edinburgh and want to try out a $39 test for free, email me by 15 November. Has to be worth a try!
The number one advice point is the fundamental one you can't afford to ignore - Clarify your goals and how you’ll use results. If you don't do this while you'll get some useful experience, your findings are unlikely to go very far.
12 Tips for Top Test Results from usertesting.com