The world celebrates a major historical milestone this week. Fifty years ago, on July 20, 1969, Neil Armstrong became the first human to step foot on the moon.

I once had the rare opportunity to have dinner with Armstrong. He regaled me and my friends with stories of the moon mission. Armstrong, a humble man, gave credit to the 400,000 scientists, mathematicians and support staff who made it happen. He also said that one leader in particular inspired him and the others--John F. Kennedy.

Kennedy had a tough sell. He had to convince Congress and the American public to spend what was--in 1961--a staggering sum of money to fulfill his vision. Kennedy's vision also required scientists to accomplish a task they thought was impossible--at least in the near future.

Like many entrepreneurs, Kennedy didn't have a working product to show off.  But he did have the power of persuasion. 

1. Be specific

On May 25, 1961, Kennedy made his vision public with this specific statement: "This nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth."

In one sentence, Kennedy challenged the nation to pursue a massive and daunting project. It wasn't an abstract goal. It was so specific, it even came with a deadline attached to it. Kennedy--a gifted writer and speaker--knew that it's easier to rally a team around one concrete mission than to divide their attention and confuse their objectives.

The motivational speaker Tony Robbins that says that a goal is a dream with a deadline. People don't get excited about generic goals. "I'm going to lose weight" is not nearly as specific as "I'm going to lose twenty pounds in four months."

Specific goals focus your energy and also serve to rally a team if the goal is a tied to a company project. For example, your team won't rally around the goal "to be the best." As a leader, you need to be specific and answer questions such as: What does it mean to be the best? In what category? Using which metric? By what date?

Be specific to be persuasive.

2. Be bold

Small goals don't inspire. If you're going to dream, you might as well dream big. "At a basic level, the president's Apollo decision was to the United States what the Pharaoh's determination to build the pyramids was to Egypt," writes historian Douglas Brinkley in his bestselling book, American Moonshot.

Kennedy didn't sugarcoat the money and commitment it would require to turn his vision into a reality. In his first speech to Congress he acknowledged that no single space project would be more difficult and expensive to accomplish.

In a famous speech at Rice University the following year, Kennedy went further, steeling the audience for the challenges requires to step foot on the moon. He called it a hazardous and dangerous adventure, but then rallied people around a common purpose and a sense of adventure. "Many years ago, the great British explorer George Mallory, who was to die on Mount Everest, was asked why did he want to climb it. He said, 'Because it is there.'"

A bold goal doesn't mean an impossible goal. Here's the key. When Kennedy gave his first speech, the timing was right. The rocket technology required to reach the moon was already under development. Yes, the project would require a combination of talent and money unlike anything the American public and its government had ever seen, but it was possible.

Stretch goals are, by definition, demanding. But they must be attainable. 

3. Celebrate milestones

The moon was landing was divided into sub-projects with their own deadlines: Project Mercury, Project Gemini and Project Apollo. Although Kennedy wasn't alive to see his vision become a reality, he did publicly celebrate each step of the mission in the early stages of the project.

People need to see that they are making progress on their goals. Weight loss experts recommend that clients break up their long-term goal into milestones that seem less daunting. Each step is accompanied by a small reward. At startups, you'll see teams ring a bell with each new sale or enjoy dinner and drinks to mark a significant achievement.

Small rewards keep your energy high for the long run. 

Nothing great happens without an inspiring leader who articulates a vision that challenges the status quo and unleashes our collective imagination. Use Kennedy's 3-part strategy to launch your own moonshot.