As a leader, you're naturally aware of the need to plan your meeting's content to keep people on track and maximize impact. But how do you respond when the unexpected happens?

Learning to deal with the unpredictable in meetings can be critical for your career. It might be the only time you're in front of a senior executive and your next remarks could either be the perfect opportunity to showcase your executive presence or go down in flames. Do you want your off-the-cuff answer to look, well, off the cuff, or come across as sharp and on target?

One of the best things I did at the start of my career was to master the art of impromptu speaking. Through Toastmasters meetings, I practiced something called Table Topics every week for seven years. Table Topics is an exercise in which speakers are assigned a random topic by a moderator and then must speak immediately for 60 to 90 seconds. Not only do you improve by repeatedly being put on the spot with no advanced preparation, but you also learn from other participants' feedback.

When I worked at Microsoft, I found myself in frequent reviews with Bill Gates and other senior executives. Because of the Table Topics training, I was always able to answer their questions calmly and professionally, even when I didn't immediately have the information they needed.

To improve your impromptu speaking and increase your executive presence in the moment, follow these simple do's and don'ts:

1. Do buy time

Stalling allows you to think about how best to respond. You can take a drink of water to make your pause look natural, repeat the question as the first part of your answer, or ask clarifying questions before responding. As a bonus, being slow and deliberate in your response can make you appear more thoughtful and strategic.

2. Do have a go-to format

Before your meeting, think about a structure for an impromptu response. Even though you don't know what you'll put into the framework until the last minute, going to a meeting armed with a couple of choices for structure helps you to be better organized so you can respond faster and with greater clarity.

Introduce a list. State that there are, for example, three elements to the topic. Even if you haven't figured out exactly what those elements are, by declaring the number up front, you can focus your attention on identifying them.

Choose one key point. Use one central idea to frame the rest of your discussion. This focuses your brain on that point and helps eliminate the noise from other, less salient details.

Use the five 'W's. Journalists are taught to approach a story by answering the five 'W's: who, what, when, where, and why. This helps your proactively answer many standard questions from your audience.

3. Do tell a story

Examples bring points to life. Think of what you've encountered recently relating to your point and share a concrete example in the form of a story.

4. Do seek feedback

After your conversation is over, seek out a supportive colleague for feedback on your impromptu speech. Don't just ask for what you could improve; also ask specifically about what you did well. The latter will help you identify the structure and processes you might adopt as your default. Partner with a trusted colleague or join Toastmasters to strengthen your impromptu-response muscle through practice and feedback.

5. Don't fudge

If you don't know the answer, just say, "I don't know. I'll get back to you by Y date." When meeting with Steve Ballmer at Microsoft, I had someone on standby on instant messaging during our sessions; that way I could tell Steve I didn't know the answer but would often be able to give him a response within five minutes.

6. Don't speak fast

Many of us tend to speak too quickly when we're nervous in hopes that it will hide that we don't know what comes next. Speaking too fast just sets you up for more ums, ahs, and filler words, and gives you less time to think.

7. Don't use too many words

We also tend to ramble when we're nervous. Stop talking when you've made your main point. You can create an opportunity to elaborate by asking if your audience has any follow-up questions.

8. Don't shortchange yourself and over-credit others

There's a reason your audience asked you this question: because they don't know the answer, and they trust you to know, or to find out. Don't let imposter syndrome take over and cause you to shuttle the question off to someone else in the room right away. Sit with it for a moment, then employ a strategy.

While it's impossible to anticipate every potential pitfall in a meeting, preparing for the unplanned allows you to remain relaxed in the moment and appear poised and articulate. You'll provide more value to your audience and look like the leader you are.