With WatchOS 2, users can now use their Apple Watch as a pseudo-alarm clock with Nightstand Mode.
To activate this feature, go to the Settings app on the Apple Watch. Next, go to General > Nightstand Mode and toggle the switch into the “on” position. From here on out, you can use the Apple Watch on its side to keep tabs on the time, date, remaining battery percentage, and any upcoming alarms. Cleverly, when an alarm goes off, you can activate snooze by pressing the digital crown.