"All right, that's it. Any questions?"
That's how most people end their speeches. And it's kind of like a car going down a highway. Everything's fine, 70 miles an hour, and then it just runs out of gas. That's not the way to end your presentation, because it makes you look uncomfortable. It is too abrupt, and it seems like you just can't wait to get out of there.
That's not the way to end your speech. Now, you don't have to end with some tear-jerk story. You don't have to end with something really funny. But end with finality. Restate your major points. Conclude. Let people know what you want them to do. And then stop, smile, and step back. It really is that simple.
Then, if you want to take questions, you can take questions. But don't just, "That's it, any questions?" Too abrupt. End with finality. With a summary.