Once you decide to launch a podcast, you’ll need to make a series of decisions, including format and structure. Your goals and podcast style should work together. You have lots of options, and can play around and figure out the best style for you. 

Format

Podcasts can have seven basic formats. They are:

• Monologue/single host: One host who talks directly to listeners. These are easy to schedule since it revolves around one person’s calendar; and they’re relatively easy to edit. Success depends almost entirely on the personality, name and dedication of the host and the strength of his/her network.
• Conversation/multi-host format: Multiple people discussing a topic with no dedicated “lead.” These can be high energy, informal conversations among “friends.” This is slightly more difficult to schedule and significantly more difficult to edit as hosts can talk over each other and go on tangents. Success depends on the chemistry of the hosts and the strength of their networks.
• Interview format: One or more hosts interview one guest. These position the hosts as experts, even if they’re borrowing their guests’ credibility. The host’s job is to find interesting ways to get at the guest’s expertise. It can be challenging to get guests booked and scheduled and requires research and guest prep, but the tradeoff is a continual set of fresh perspectives and guests who can share the episode with their networks.
• Panel/roundtable format: One moderator asking two or more experts a series of questions on a specific topic. Each additional guest multiplies the pros (number of perspectives, potential audience reach) and the cons (difficulty of scheduling, amount of editing, guest prep and research).
• Scripted fiction format: Similar to an audio book, where each episode is a chapter, this is a highly produced piece of audio theater. This takes a significant amount of time, money, planning, creativity and preparation. If done right, they can reach a wide audience, eagerly anticipating the next episode.
• Investigative/nonfiction format: A great way to educate listeners while entertaining them. This takes a lot of preparation and research. You can tell a story over multiple episodes, or each episode can be its own self-contained report. This can build a highly engaged audience, but requires a high production value.
• Live/Repurposed content format: the audio/video is pulled from a live or pre-recorded in-person or online event. The editing here can be light (just tack on and intro and outro) to heavy (adding narration, cleaning up misstatements and extraneous words). You can also split up one event into multiple episodes. The major concern is audio quality.

Structure

The basic structure of a podcast is Introduction, Body, Close. But you can also break the body into multiple segments, each with it's own unique purpose. And, you can add a sponsor or ad break between each. Keeping your structure consistent will help listeners stay oriented while you change tones, guests, topics, etc. Again, the key is consistency.

Tone

Tone is the mixture of vocabulary, pitch and cadence. Choosing the right tone is a balance of your personality, your topic and your target audience. The better you know all three, the more successful you’ll be at figuring out your tone. Here are some ways “tone” can make you and your show sound:

• Journalistic (authoritative)
• Educational (knowledgeable)
• Storytelling (descriptive) 
• Reassuring (friendly)