Broad question given the nature of wearable technology (largely dominated by heads-up displays such as Google Glass and smart watches such as the Pebble), but what would the user experience guidance for such technology look like?
I would say they'd begin to take shape along the lines of something like...
- Ensure the device "fits" the wearer (user) and not the other way around. Do not require changes in established user task behavior (e.g., we know how to glance at a watch or to look through Glass).
- Design for an experience that is unobtrusive to wear and use in context (i.e., no scaring of the natives!).
- Assume multiple device integration for task completion (smartphones, wearables, desktop). In other words, an optimized UI for this context of use might be supplemented by other UIs elsewhere in the task flow.
- Use natural gestures and actions for operation (think the swipe down action on Glass for "back button", or the tapping of watches).
- Integrate technology for object capture, context, and sharing (QR codes, camera for images or video, voice-to-text, augmented reality, GPS).
- Use visualizations and iconography simply and consistently (LEDs lightups, Dashboards, info cards, drill-downs, and so on).
- Provide for important information display only, minimally.
- Enable personalization (think select notifications and alerts on watches).
- Allow for different modalities of use (voice or gesture on Glass, wink to capture images AND "OK, Glass..." voice command approach to capture too).