It is possible that in the exam you may be required to write a podcast.
I think it is useful to consider a podcast as a discreet digital audio broadcast that can be downloaded onto a computer and stored to keep.
This may take a variety of formats. For example a monologue or a form of dialogue probably in the form of an interview.
It will be up to you to decide which format is most suitable for the recasting task.
I think it is best to consider your text as a script for a podcast either as a monologue or interview dialogue. Consider that your main purpose will be to inform and entertain. But do not rule out the possibility of persuasive or imperative writing.
Click here for a link to examples of Radio 4's programme, The Today Programme podcasts.