Don't expect one radio show or one webinar or one advertisement or one social media event (e.g., a live FB event) to bring a swarm of customers. The market doesn't behave that way. Repeated media exposure is what gets clients swarming to you. About 7 media exposures are necessary to create momentum and start the snowballing effect.
Let's say you were invited to a radio interview. As you prepare for your radio stint, do not hold the intent of attracting many customers with one radio show, otherwise you will come out "salesy." Instead, COMMIT to the intent of connecting with your audience and winning more invitations to speak, the ultimate goal being repeated media exposure. With that intent in mind, you'll end up speaking as an authority/expert in your field rather than as a sales person. The Golden River flows where your intent goes.