Visual Slides and PechaKucha

Meera's draft slide for the accuracy part of her talk has a title, "Why Rainkit?", and seven bullet points in full sentences. When she tests it on a colleague, he reads the slide instead of listening to her, finishes before she does, and then looks at his phone. The slide is competing with her, and winning.

The rule

One idea per slide, shown rather than written.

People can listen or read, but they do not do both well at the same time. A slide packed with sentences splits the room's attention, and your voice loses. So each slide should carry one idea, and carry it visually wherever possible:

• A big number: "1,000 calls a day, free", in large type.
• A simple diagram: app → request → Rainkit → JSON → alert.
• A chart with one clear point, labelled directly.
• A photo that sets the scene, such as a soaked delivery rider.
• Code cut down to the few lines that matter, in a large font, with the key line highlighted.

The words you want to say go in your speaker notes, not on the slide. And everything on screen must be readable from the back row: large fonts, strong contrast, no tiny screenshots.

PechaKucha takes this to an extreme. The format was created in Tokyo in 2003 by the architects Astrid Klein and Mark Dytham, and its rules are simple: 20 slides, each shown for 20 seconds, advancing automatically. That is 20 × 20 = 400 seconds, or 6 minutes 40 seconds, and you cannot stop or go back. Text-heavy slides are impossible in 20 seconds, so the format forces one visual idea per slide and a tight script. Even if your real talk is 30 minutes long, building a PechaKucha version is an excellent drill, and many meetups run PechaKucha or lightning-talk nights where it is the whole format.

The shortcut

Use the glance test: show the slide to someone for three seconds, then hide it. If they cannot tell you its point, simplify until they can.

Drills

Answer fast — trust the rule.

Remember

• One idea per slide, shown rather than written.
• Shortcut: the glance test. If someone can't get the point in three seconds, simplify.
• Trap: slides as your script. PechaKucha, 20 slides × 20 seconds, is the drill that cures it.