EDIT.
By this, I mean - don't think that a continuous stream of rambling is always a wise idea. You can maintain good audience retention and cut the length of your videos in half if you edit out all the times you say "uhh" or "uhm" or something that isn't really important.
Write a basic outline of what you'd like to cover, and make sure you stay on track. Your videos will instantly look more polished and interesting if they're to the point and don't look lazily put together.