If you know nothing else about Martin Luther King Jr., I guarantee you know this:

"I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin, but by the content of their character."

It's probably the most famous and most inspiring quote from his most famous and enduring speech, one that winds up on just about every list I can find of the top speeches of the past 100 years--or maybe ever.

King would have been 88 years old had he not been cut down by an assassin's bullet almost 54 years ago. As we remember him, here are 7 things to emulate from his success as a speaker (especially citing the "I Have a Dream" speech).

1. Speak with moral authority

King's entire career was dedicated to civil rights, specifically for African Americans. It's perhaps the single greatest moral cause of our maturing American democracy. His speeches pack more power at the outset because they're focused on important moral issues.

Takeaway: Enduring speeches have an enduring moral core. The content of your character is most important.

2. Make personal connections

King doesn't just dream for America. He dreams for his family: that his "four little children" will grow up in an evolved country. It's tricky to make personal connections, because you want your speech to inspire the audience, not just discuss your personal viewpoint or ambition. But King does it well.

Takeaway: Embrace your audience's humanity, and yours.

3. React to the audience

During the speech, a famous gospel singer can be heard calling out, "Tell them about the dream, Martin!" It appears (although maybe not accurately, for reasons we'll see below) that King changes his cadence in response to her entreaty, and starts the "I have a dream" refrain. Regardless, his connection to the audience increases as a result.

Takeaway: A great speech almost becomes a conversation. Find a way to incorporate the audience.

4. Speak in poetry

King uses the phrase "I have a dream..." 12 times during his speech, including nine times in a row to begin the succinct paragraphs for which it is best known now. It's poetic. In fact, I encourage you to watch at least the first few seconds of this part of the speech on YouTube. At points, his cadence and tone shift to the point where he's almost singing the lines, rather than simply speaking them.

Takeaway: A speech is a performance. You don't need to be over the top, but it helps to act like a performer.

5. Choose your audience

True scholars and educated followers of King often say "I Have a Dream" is a wonderful speech, but not his most important speech in the context of his work. So why does it endure? One reason is the setting: He was speaking on the steps of the Lincoln Memorial, in front of a crowd of 250,000 people, broadcast on national television.

Takeaway: Choose your moments, and seek the greatest audience you can find.

6. Practice and refine

King was an incredible orator, but this wasn't the first time he'd delivered a version of "I Have a Dream." In fact, he'd been using variations of the phrase and the rhythm in multiple appearances, and historians recently found a recording of a very similar speech--with the same refrain--that he'd given at a high school in 1961. Reportedly he was up until 4 a.m. the night before the speech, rewriting it again.

Takeaway: Don't let your first effort be the one you make on your biggest stage.

7. Learn from the masters

Before "I Have a Dream," King told people he hoped to deliver "a sort of Gettysburg Address," harkening of course to another incredible American speaker, Abraham Lincoln, a year before. Now King himself is one of our icons of oratory.

Takeaway: Study and learn from the masters. They're easy to find.