You can use Spotify, Itunes etc to start a podcast and when you do start a podcast be sure that what you're talking about on the Podcast is quality informative content that people will want to share and promote your podcast for you.
Once you get enough audience for your Podcast you can get paid by sponsorships and advertisements and even sell your podcasts for download when people know that your content is good then they'll likely pay for an even more informative podcast.
So you could give out some good information on a free podcast and then have the people purchase the addition information through another paid downloadable podcast.