If you’re interested in getting up and running with your Apple Watch quickly, there's an excellent resource you can spend time with when you aren't hitting refresh on the UPS tracking page. There’s a nice infographic by Redditor macamacamac showing the chain of actions used for basic navigation, as noted on the latest Maccast episode by our own Adam Christianson. That image:
Apple Watch Navigation by redditor macamacamac
(Click for a larger version, or view the original on Imgur)
There's a lot to go over, especially since the try-on appointments only include a "demo loop" so there's not an opportunity to really try out the interface, just the watch and the band.
As would be expected, most things start from the "Watch App," since that's what comes up when your arm comes up, waking the screen. While in the Watch App, you can swipe down from the top for Notification Center, much like the lock screen on iOS. Swiping up from the bottom offers Glances, which appear to be compact displays of information like weather and the Stock app. These screenshots indicate a large number of dots at the bottom of Glances, so this appears to be where most of the information offered by third-party apps will ultimately end up.
Moving on from the Watch App, if you swipe from left to right you'll get to customize the watch face, including the display of time and the activity or other smaller info panels as shown in the ads and the guided tours. Once those are customized, swipe right-to-left back to the watch app, and then again to get to the apps screen.
From the apps screen, you can move around by swiping, and then launch the app either with a tap of your finger or with the Digital Crown. Once you've launched an app, you can scroll up and down using the touch screen or the Digital Crown. Force Touch on the screen will take you to the settings or other options for the app. Another Force Touch will take you back to the app itself. From the app, you can return to the apps screen by either swiping or pressing the Digital Crown again.
Three apps can be accessed from anywhere: Apple Pay by double-clicking the side button, Favorite Contacts with a single click of the side button, and Siri with a long press on the Digital Crown.
How Notification Center actually works is familar to iOS users. Much like on an iPhone, notifications can be acted on, dismissed, or used to open the app itself.
App Switching works slightly differently than on iOS, with a double-press on the Digital Crown letting you switch between the two most recently opened apps, not display a long line of recently opened apps (whether they are still running in the background or not).
Between this graphic and the guided tours, it seems like people will be well-prepared to interact with their new watches once they arrive. For those who would like additional help, there's always the workshops offered in Apple Stores to help people get going.