Look at the frame from this Reel: big face, giant text, nothing else fighting for attention. That is exactly how your billboard should feel. One idea, shouted loudly, so a speeding driver can “get it” in half a second.
Turn your best benefit into 3–7 bold words, just like the captions in the Reel. Pair it with a close‑up face and a tiny, simple CTA (URL, QR, or short code). If someone cannot read and understand your board in three seconds, delete stuff until they can.
Apple uses giant photos with two words, “Shot on iPhone,” to sell camera quality from a moving car.
The Economist runs billboards with one clever line on a red background to signal intelligence in a single glance.