Intermediate10 min

Generate Thumbnails, Images, and Short Video Clips

Words are only half of content. This lesson covers the visual half: thumbnails and post art with Midjourney or Flux, and short generative video clips with Runway or Kling for b-roll you cannot film. Used well, AI media removes your single biggest production bottleneck.

Step 1: Thumbnails that read in half a second

  • One focal subject, big and clear. Clutter loses on a small screen.
  • At most a few words, large enough to read at thumbnail size.
  • Contrast with the title; the two should not repeat the same words.
image prompt (Midjourney / Flux)
Bold close-up of a single sizzling cast-iron pan on a dark counter,
dramatic side lighting, steam rising, high contrast, empty space
on the left third for large text, photographic, --ar 16:9

Step 2: Generate b-roll you cannot film

Runway and Kling turn a prompt or a still image into a few seconds of motion. Use it for cutaways, abstract transitions, or shots that would be impractical to film. Keep clips short; current generative video looks best in two to five second beats.

Runway - generate
You
Animate this still: steam slowly rising from a hot pan, gentle camera push-in, 4 seconds.
Agent
Generated 4s clip, 16:9. Subtle push-in, steam motion looks natural. Ready to download or extend.
Image-to-video for a cutaway you would otherwise have to film.

Step 3: Refine the winner with real type

Image models are a sketchpad, not a finishing tool. Generate compositions fast, pick the strongest, then add real, legible text and your face if your channel uses it. Faces and clean type still drive clicks more reliably than a fully AI-rendered scene.

Disclose and check rights
Some platforms ask you to label AI-generated or significantly AI-altered media, and many regions are tightening rules through 2026. Know your platform's policy, label when required, and avoid generating real people's likenesses without consent.

Example result: two genuinely different thumbnail concepts and a handful of three-second AI b-roll clips, produced in under an hour, that would have taken a full shoot day to film.

Hands-on tasks