If you've got 3 points to make or 12 slides to cover, practice moving from one to the next. A transition can be as simple as a rhetorical question that leads into your next point. Or, take that question and turn it into a statement. You can bridge topics with stories or build from one topic to the next. Work on the transitions, or you may sound lost in your own talk.
Bookends bracket an important idea, making longer explanations easier to digest.
Think about your presentation as a book with characters, chapters, and themes. Stories provide the characters, transitions divide the chapters, and bookends highlight the themes. Sketch out your talk on a piece of paper. Then I introduce those points up front. Finally, I fill in the middle.