Build the response into the encounter
Give audiences something to do within the advertising experience, rather than only a message to receive. Participation can turn a one-way communication into a two-way encounter, whether the action is entering a competition or booking a test drive. An early interactive Mazda advert encouraged viewers to record the advert and replay it frame by frame to take part in a competition to win a car. In 2020, an Audi advert allowed listeners to talk back through their smart speaker and book a test drive. The practical principle is to build the intended response into the format: the audience should have a clear way to act, not simply encounter an invitation to act elsewhere.
Sources: 100 years of the BBC… sort of