A critical presentation. A key meeting. An broken customer relationship you need to repair. Whatever you’re about to do it’s incredibly important… which makes you incredibly nervous.

To perform at your best, what you need is a quick dose of confidence — which might take more than simply reading inspirational quotes to increase your confidence. (But then again maybe not — check ’em out.)

While true confidence takes time to develop (because true confidence is based on incremental, steady success), fortunately there are ways you can quickly overcome your anxiety and nerves and perform well:

1. Burn off some chemical stress.

When you feel anxious or stressed your adrenal glands secrete cortisol, one of the chemical triggers of the instinctive fight-or-flight reflex. High levels of cortisol heighten your emotions, limit your creativity, and reduce your ability to process complex information. When you’re “high” on cortisol you get tunnel vision just like you do when you’re startled or scared.

Here’s what to do: Burn off excess cortisol with exercise. Take a walk at lunch. Work out before you leave for work. Hit the hotel gym before your meeting.

Don’t think it will help? Remember a time when you were totally stressed and decided to work out. When you finished exercising felt a lot less anxious and a lot more grounded. The perspective you gained came at least in part from lowering your cortisol levels.

2. Eat the perfect “pre-game” meal.

Dopamine and epinephrine are two chemicals that help regulate mental alertness. Both are found in tyrosine, which is an amino acid found in proteins.

Here’s what to do: Make sure you include some type of protein in your pre-game meal. And don’t wait until the last minute to fuel up — the last thing most of us want to do when we’re nervous is eat something healthy.

3. Prepare for a few “What if?” possibilities.

If you’re like me, the “What if?” stuff is your biggest worry: what if PowerPoint crashes? What if my time gets cut short? What if someone constantly interrupts and screws up my flow?

Fear of the unknown is a confidence killer — and can quickly spiral out of control.

Here’s what to do: Think about some of the worst things that can happen and create a plan to deal with them. Then you’ll feel more confident because you will have transformed, “What if?” into the much more positive, “Okay, if that happens all I have to do is…”

Plus simply going through the exercise of planning for different scenarios will make you better prepared to think on your feet and adapt if something unexpected does occur.

4. Go beyond your lucky socks.

Superstitions are a vain attempt to control uncertainty or fear. Wearing lucky socks doesn’t really make anyone perform better.

Here’s what to do: Instead of creating a superstition, create a pattern that helps you prepare and emotionally center yourself.

For example, I like to walk the hall before a speech to check audience sight lines. Maybe you will decide to always do a run-through of your presentation an hour before you go on even though you’re sure you can do it in your sleep. Or maybe you will decide to run your demo one last time before every client meeting, even though you’ve run the same demo dozens of times.

Pick certain actions you will perform — actions that are actually beneficial and not just based on superstition — and do those things every time.

Comfort lies in the familiar, and so does confidence.

5. Establish a secondary goal.

Say you’re speaking to a group and your goal is to convince members to donate time to a worthy cause. Pretty quickly you realize almost no one is listening, much less cares.

What do you do? You flounder. Maybe you try too hard. Or maybe you give up and just go through the motions. Whatever you do, you walk away feeling like you failed.

Here’s what to do: If you know what you really want may be hard to get, always have a secondary goal in mind. Plan for success but also plan to turn total failure into partial success. If you can tell you won’t succeed with your primary goal, be prepared to plant seeds for another attempt down the road.

Say you have an idea and want upper management to okay your project. Midway through you can tell they won’t say yes right away (after all, they almost never will.) Be prepared to shift to laying the groundwork for future meetings. Explain what you’ve done and what you plan to do even if your project isn’t officially sanctioned. Lay the foundation for the people in the room to see future possibilities. Lay the foundation for them to develop a sense of trust in you and your idea.

Sure you may want them to say, “Approved!” Shoot, you may need them to say, “Approved!” But you should still be ready to turn a one-time meeting into a series of meetings.

Whatever your primary goal, establish a secondary goal so that instead of losing all faith in yourself and your mission you’re ready to transition to that goal. If things aren’t turning out the way you hope you’ll still be able to stay confident — and keep moving forward.

This article is published in collaboration with LinkedIn. Publication does not imply endorsement of views by the World Economic Forum.

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Author: Jeff Haden is a Ghostwriter & speaker as well as a contributing editor at Inc. Magazine.

Image: A man walks along an empty street near the central financial district in Hong Kong. REUTERS/Carlos Barria.