Avoid introductions like, "Hey everybody, John Lindquist again from Egghead.io," or even, "Let's look at how to add RxJS to View." Instead, just start doing it.
Install your packages. Import the module. Type out the required code to use it. Leave the description or introduction down in the description of the lesson. If they need an introduction they can read that.
Then, at the end of your lesson avoid saying, "Goodbye," or, "In the next lesson we'll explore how to do X, Y, and Z." Instead, the next lesson will show up in a playlist or, if it's part of a course, it will automatically play.
So there's absolutely no reason to say, "In the next lesson we'll cover X, Y, and Z," if that next lesson will start and a title of, "How to do X, Y, and Z," pops up then they're already there. It's all about respecting your audience and not wasting their time.