Every Friday, we invite a creative professional into our studio to share what they’re working on. Last week we hung out with Ben Lillie, a writer for TED and a cofounder of Story Collider, an organization dedicated to live storytelling by people involved in and affected by science. Following our discussion, we distilled these six tips for delivering effective, engaging presentations:

1. What’s the point?

When he’s workshopping talks with Story Collider presenters, Lillie makes the distinction between the story and the point. Every presentation must have a point—the big idea the speaker is trying to convey. Stories don’t necessarily have to have one. They can simply be about a character’s emotional transformation.

2. Find the emotion.

The biggest factor in the success of a story is whether the storyteller tells it with feeling and the audience can tell there’s an emotion attached. It can be subtle, but there have to be real stakes.

“You look at a story and something funny happens or something amazing happens, but not much is riding on it,” Lillie says. “To take a a ridiculous example, you can say ‘I saw a giant whale,’ but unless it’s about to kill your mom, it’s hard to get excited. That emotion can be anything from ‘my dad is sick and dying‘ to Matt Danzico’s story about strangers on the internet.

3. Give it a structure.

Stories need to have an arc. The storyteller either needs to start at a low point and end at a high point or start high and end low. “You can’t have someone be awesome and then have something more awesome happen to her,” Lillie says. “At Moth Story Slam they say begin by defining a story as something with a beginning, middle and end. That sounds like the most basic thing, but it’s surprising how far you can get with that. Ninety per cent of workshopping is finding the the beginning, middle and end and putting them in that order. It’s basic but worth remembering again and again.”

4. Think hard about using visuals.

You may not need them at all. At StoryCollider and the Moth, no visual stimuli is permitted. “If all you have is the speaker on a blank stage, it forces the audience to look at only that person,” Lillie says. “It’s similar to radio. This is why This American Life works so well but had trouble translating to TV. You want to require the audience to create the imagery in their minds.”

5. Be natural.

The single easiest way to fail is when the presentation is overwritten and sounds rehearsed. “You get this a lot from writers in particular because they are trying to get every sentence to sound perfect,” Lillie says. “If that happens you stop rooting for the storyteller. When we edit the talks for StoryCollider, we don’t really edit out the ‘ums’ and the ‘aws.’ ”

Lillie points to Kevin Slavin’s talk on algorithms, and the way his delivery hits the sweet spot between being real and relaxed. Ironically, the imperfections in his delivery make the performance more resonant. Researchers at McGill University identified significant “speech doubling”—a stutter, essentially—in Slavin’s talk, especially when he uses the word ‘is.’

“I watched the talk 5 times without noticing this before I read that study,” Lillie says. “It’s not intentional on his part, but it’s that little flaw that makes it work. Just being yourself is really hard because you have all these ideas about how you have to embody Ken Robinson. You aren’t Ken Robinson. It’s OK to be you. It’s OK to tell your story. We’re conditioned to think it’s not OK to do that, but people will be interested in what you have to say.”

Of course, the worst TED talks are the ones where the presenter just reads a script. These rarely make it to TED.com, Lillie says.

6. Practice.

Getting up and talking to strangers is a skill, but it’s not one you can learn in a few hours. Clocking stage time is a big part of it. There’s no short cut—you have to practice somehow, somewhere. People understand that about music, but there aren’t that many venues for practicing public storytelling.

Here is Lillie’s suggested approach to preparing a talk: write the whole thing out, then throw that away and distill it down to an outline. You want to have it written once so you know where you’re going, but you would have to be a phenomenal actor to do the script word for word in a way that sounds normal.

For those who haven’t spoken in public before, Lillie says there is something special about a speaker’s first time on stage.

“There’s incredible energy in someone who is super nervous and sometimes they can be amazing the first time,” he says. “The first time I did the Moth I thought it was incredible, but the second, third and fourth times sucked.”

UPDATE: This post originally described Ben Lillie with experience workshopping presentations with TED speakers. In fact, he only workshops with Story Collider storytellers. He says, “I think of myself as the founder of Story Collider first, and my TED work is supplemental to that.”