Your current listeners are the best PR team to increase audience growth. Get to know your current listeners. They'll tell their friends about your podcast. Find out what their interests and habits are. Get them to tell you what they want your podcast to do. This way, you can fine-tune your podcast to increase your audience and reach more listeners.
I'm not suggesting you take each individual listener out for a chat over a cup of coffee (though that would be very nice of you). The best way to get the information about your audience that you need, is with a short and carefully crafted podcast survey.
Podcast Survey Tools For Growth
I like a free tool as much as the next podcaster, so let's start with a couple of them. And I'll include one paid option if you want to really ramp up your data gathering.
Google Forms has a gallery of templates which you can use to create a standard type of form. It's easy to use, and everyone knows the brand, so it's pretty low-barrier. The look is, for me, a bit dated, but it's totally adequate for your average survey.
SurveyMonkey is a lot more flexible. It's a paid product, normally, but the freemium tier will let you make a short podcast survey with ten questions or less, for nothing. If you don't need to go long, or need any of their other premium options, it could suit well.
Paperform is my final recommendation, for those who want the full power of a paid product. Full flexibility and a range of beautiful templates, you can make a survey that looks great and really draws people in.
One of the best Paperform features is the ability to create what they call a ‘landing form.' In plain English, it's a page creator that includes survey elements, so you can build a great looking ‘audience welcome page' which asks them questions, gets your data, but also gives them a bunch of value through episode guides, downloads, contact info and more. You can build a place where you give as value them as they give to you in filling in their data.
You really don't want your podcast survey to be longer than ten questions. Your listeners are already giving you their time and mental effort. Ask for a little, and you'll get a lot.
Multiple-choice questions will get you results that are focused and specific. Open-ended questions can give you results you hadn't expected. They can also lead listeners to use them as a personal soapbox or open-mic night. Limit the amount of characters responders can use, so they have to keep their response short.
Read the guide at Running an Audience Survey
Check out the full book - Podcast Growth: How to Grow Your Podcast Audience