"Best man"

Yeah, actually, I have Public Speaking right now this semester! I did an introductory speech to introduce a person, but I've yet to practice on doing a toast.

I'd flip through your textbook and look for "speeches to entertain" or something like that. Did a quick Google search and found this nugget of goodness:

... select a central theme, just as you did with informative and persuasive speeches. But here, remember that your audience just wants to have fun. Your topic should be genial, good-natured, and suited to you: after all, if you're not having fun, how can anyone else party hearty?

Your overall theme should be …

* Optimistic. This is not the time to unburden your soul and let it all hang out. Keep it light.
* Uncomplicated. Don't make your audience do any heavy lifting to get your point. Instead, develop your speech around one or two points that your listeners can grasp easily.
* Lively. Select a theme that can be illustrated by pertinent anecdotes and humorous stories (if humor works with your comfort zone).

But wait! Every entertaining speech, no matter how light and amusing, should have at least one serious point. A speech that's all sweetness and light can border on empty. Including one serious point serves as an anchor, so people feel like their getting their money's worth, like the prize in the Cracker Jack box.