Before you rush into things, it’s important to keep in mind that podcasts take a lot of effort to get going. They’re not just recordings of people talking (not the good ones, anyway).
It’s easy to assume that podcasts are easy to produce because they’re audio only, but don’t be fooled. They can take a lot of time to put together, especially at first. Also, if you’re interested in developing any kind of listener base, you have to be ready to release episodes on a regular basis. All in all, podcasting can be fun work, but it’s still work and should be treated as such. - Source: lifehacker
You need to know why you are starting the podcast. What are your goals? What will you talk about? Determine this early in the process, and research other people doing the same thing. If content overlaps, don't fret. Just take a step back and try to come at it from a different angle. Make it your own.
You also need to determine your voice. What kind of persona will you portray? It's easy to think, "I'll just be myself," but what does that entail when you factor in professionalism and your agency's brand? Brainstorm with your other host(s) and come to a decision before delving into the rest.
Podcasts range from very short to an hour or more. Make sure to ask: “How much time does your audience have to listen?” We try to keep our podcast around 20-25 minutes. Several sites state that listeners tend to listen to about 22 minutes of a podcast.
There are several ways to approach this. We go into more detail under the Making a Podcast tab.