You are probably making one of these 7 mistakes in your everyday speech

We each speak about 16,000 words a day–almost all of them delivered off the cuff. Some might roll off our tongues in the elevator, others are spoken in meetings, and still others flow out of on-the-fly conversations like corridor chats.

Wherever you are—whoever you’re with—your spontaneous words matter. They define your personal brand and professional image. It’s a good idea, therefore, to master off-the-cuff speaking and avoid the typical traps that so many of us fall into.

The following are the seven deadly sins of impromptu speaking. Commit them, and you’ll undercut your image. Avoid them and you’ll strengthen your leadership.

1. Speaking before thinking

Topping the list of impromptu sins is speaking before you’ve collected your thoughts. Winston Churchill joked about such speakers: “Before they get up, they do not know what they are going to say; when they are speaking, they do not know what they are saying; and when they have sat down, they do not know what they have said.”

Talking before formulating your ideas makes you sound sketchy. The words flow, but the ideas are half-baked. And you’ll find you have to resort to such phrases as, “So what I’m saying is,” or, “As I said before.” Want to avoid such gobbledygook?

Prepare to be spontaneous. If you know you’re going to meet with your boss, jot down a set of bullet points that make your case. If you’re in a meeting and want to contribute to the discussion, pause, formulate your message, then speak up. If you see a colleague coming down the hall, think, “What point do I want to make with her?” In short, think before you speak.

2. Running off at the mouth

A second off-the-cuff blooper is talking too much. Interrupting others, monopolizing a meeting, or going on and on far too long turns people off. I once contacted a Humane Society to see if there was a way I could give a gift in the memory of my pug. The person who picked up the phone said there was a campaign under way, and “If I could just take three minutes of your time, I can tell you what the options would be.” Twenty minutes later, I had to go, and never did find a clear path to giving a gift.

Blathering usually reflects a failure to structure your thoughts. The solution: Establish your structure at the beginning and stick with it. If you’re going to give “options” or “reasons,” stay with that pattern of organization. Don’t digress or let your motor mouth derail you.

3. Experiencing mind freeze

A third impromptu failing is the opposite of saying too much–it’s freezing up. Your mind goes blank and you’re completely at a loss for words. This can happen out of nervousness, anxiety, or lack of preparation. It often happens in intimidating situations when we’re worried about how the other person is judging us. One client told us she experiences “brain freeze” when she presents to senior executives. She’s afraid of being criticized, so she mentally retreats.

The solution is preparation and more preparation. If you know you’ll have to face a particularly trying situation, say, presenting to top management or going for a job interview, role play the situation with a friend. Ace the rehearsal and you’ll find your brain freeze will thaw.

4. Um-ing and Ah-ing

Another impromptu no-no is using filler words like “um,” “ah,” “well,” “like,” “you know,” “yeah,” and “to be honest.” They’re distracting, and make you sound hesitant and unsure. For example, if you say to your boss, “I think, um, I’ll be able to, ah, get that report in you know in time for the committee meeting,” your boss will not be convinced.

People use filler words when they’re thinking through their statements. They use “ums” and “ahs” to plug the pauses. Your listeners need the pauses to think about what you’ve just said. Filler words are a big annoyance to your listeners.

Want to rid yourself of these pesky expressions? Listen to yourself. Record yourself. And replace the filler words with silence. You’ll discover that pauses will make you sound far more decisive and thoughtful.

5. Putting your foot in your mouth

The fifth sin of impromptu speaking is saying something you’ll regret. We all carry around in our minds disappointments, battle scars, and uncertainties. Sometimes it’s hard to divest ourselves of these negative feelings. So we say things we regret.

A manager told me of an unfortunate outburst of hers. “Before leaving for work,” she said, “I tripped over the dog, spilled my coffee, and got delayed by traffic. So when my assistant told me, ‘Today’s the day we’re making that change to the internal software platform,’ I lost it. I said, ‘Oh, that BLEEP BLEEP platform.’ Two of the junior people on my team passed me and knew what I was referring to, making it harder to pitch that platform because I had slammed it.”

Realize that even in the most casual situations–especially when your team members or colleagues are listening–you want to speak as a leader.

6. Flubbing the facts

Still another transgression of impromptu speakers is not getting their facts straight. A sales executive I know was presenting to a client, and he had a junior team member with him. The presentation went well, then came Q&A time. An attendee asked what the cost would be if certain modifications were made in the product. The underling piped up, “That will be an additional 10%.” Unfortunately, the changes would actually have cost an additional 20%. The executive didn’t want to correct his team member in front of the client. So the client got a great deal.

Whether you’re standing in front of a client, or talking informally to a colleague, you must get your facts straight. Know your material inside and out, and prep for any factual questions that might be asked. If a question comes out of left field, don’t guess, but instead say, “I’ll be happy to get that information for you.”

7. Checking out

A final sin of impromptu speaking is thinking of casual conversation as unworthy of your full attention. When speakers check out, their thoughts wander, they look around, or they glance repeatedly at their phone or computer.

Such movements show the speaker is not entirely “in the moment.” Think of impromptu speaking as your opportunity to lead and inspire every day, every moment. Make the most of these situations by being fully present and engaged. Use strong eye contact, stand or sit tall, align your body with those you are talking to, and don’t obsess about what’s on your computer screen, who is texting you, or who might be passing by. Give your audience your full presence, and they will listen more attentively to you.

These seven common mistakes can be avoided through preparation and understanding that these casual moments are worthy of your leadership.