Focus on the important details, such as:

• Introduction -- what the system does, and what the goals are for this study.
• The tasks that participants are asked to perform / activities they engage in;
• Significant data that was collected. This is not all the data, necessarily, in raw form, but some digested form that presents everything relevant that happened during the study.
• Analysis. What was learned? How will this impact the design?
• The affordances for notification of events in context, and for users' responses;
• How state is made visible (or audible, or tactile), or not;
• Flows of essential information, expression, and control;
• How users transition between real life and the mediated reality (e.g., engagement in interactive i/o while walking down hallways or crossing streets);
• Social aspects of experience, and how your system affects them.

A suggested approach is to carry out the process described in [3]. Rehearse on each other before you bring in your subject/friends. Realize that lo-fi prototypes can be buggy! Work to identify and fix bugs in advance. Assign the suggested roles -- such as greeter, computer, observer -- to members in your group. You may also think of yourself as conducting a workshop [1, 2]. Perform a debriefing at the end [3].

You may create whatever variations on this process you like, to the extent that you are very clear in your sense of what you're doing. Ask me (by email or in person) if you're unsure.