From the blog "The Podcast Corner"

Hello my fellow Aincradians! The time has come to open up to the community for special guests! If you want to be a guest on the podcast then this post is for you! To apply to be a special guest, you need to meet these requirements: If you have been on the podcast previously in that season, you will be invited back for any episode that has the same main topic that you have discussed. If you are still interested in applying to be a special guest, please contact me (Shark) Please fill out this application in order to be considered for a special guest If you do not make it on the podcast this season, you will be in the next season. The list will rollover to the next season. Once you are accepted as a special guest, you will receive an episode number and a TENTATIVE date. The date may change as the topic is not finalized until at least a week before the podcast. 
If you have any questions, feel free to contact me on discord, on the site, or comment below.