This is the first thing you'll want to do when using an Apple Watch
I've been using the Apple Watch for a few hours, and after 40 minutes the constant notifications started to annoy me.
The problem is that no matter what apps you have installed on your watch, the default setting is to mirror all of the notifications from your phone. That means that you'll be bombarded by tweets, Instagram likes, Foursquare check-ins, and so on.
The Apple Watch doesn't work best when it's vibrating every minute. Instead, you'll probably want to have it alert you to just the most important things.
It's not easy to disable notifications on the Apple Watch. In fact, you can't even do it on the watch. Instead, you have to fire up the Apple Watch app on your iPhone, and go to notifications.
I went through and disabled notifications for almost all the apps. But I left things like Messages, Email, and Whatsapp on. Straight away, my watch wasn't buzzing on my wrist all the time.