I can't speak for the live chat, but for notifications, you have to set it to "always" in your subscription preferences for a particular channel.
A way to do that is, once you're in a video of a channel you're subscribed to, using Chrome, you'll see the subscribed button, followed by "subscription preferences". You can then set the notifications to "always" if you want to be notified of every upload/stream, I believe it's on occasional by default.
There is one rule above all others for being a man. Whatever comes, face it on your feet.
@bcs993 on twitter, feel free to follow!