If you already write, you already have a podcast
Substack writers and researchers have the hardest part done. The gap between an essay and an episode is smaller than it looks — and it isn't technical.
If you write a newsletter, you have already done the difficult part. You have a subject, a point of view, an audience that has chosen to hear from you, and a habit of finishing things on a schedule. Those are the four things that kill most podcasts, and you have all of them.
What stops writers is rarely the writing. It is the suspicion that audio is a different craft requiring different equipment and a different personality. Some of that is true. Much less of it than people assume.
Do not read the essay aloud
This is the mistake that makes writers conclude they are bad at audio. Prose written for the eye sounds wrong in the mouth, and it isn't your delivery — it's the sentences.
Written English leans on subordinate clauses, parentheses and semicolons, all of which let a reader hold two thoughts at once and reread if they lose the thread. A listener cannot reread. Every nested clause is a place to fall out.
The conversion is mechanical, and takes about fifteen minutes an essay. Break long sentences into short ones. Replace "which" and "whereas" with full stops. Move the point to the front of the paragraph. Say the number rather than referencing the chart. Read it out once and cut anything you stumble over twice — the stumble is the sentence's fault, not yours.
If a sentence has more than one comma, it probably needs to be two sentences. If you have to take a breath in the middle of a clause, it definitely does.
Keep what makes the writing yours
The temptation in the other direction is to become a broadcaster — warmer, more energetic, more presentational than you are on the page. Readers who followed you into audio came for the thinking, and a performed version of you reads as less trustworthy, not more.
Speak the way you'd explain the piece to a colleague who asked about it at lunch. That register is almost always right, and it is the one you can sustain for two years.
Your readers did not subscribe for your voice. They subscribed for your judgement. Audio just delivers it while their hands are busy.
Publish both in the same week
The version of this that works is not a separate show with its own schedule and its own ideas. It's the same piece, in the other format, going out at the same time.
That means no new content calendar and no second well of ideas to keep filled — the two things that make a second channel collapse. It also means the audio and the essay reinforce each other: people who prefer to listen stop bouncing off your archive, and the ones who read anyway now have something to put on when they're driving.
Practically: write as usual, spend fifteen minutes converting for the ear, record in one take at your desk, let the software clean up the room, publish both. An hour on top of a piece you were writing regardless.
Start with one you've already published
For the first episode, use a piece that already did well. You know the argument holds, you know people cared about it, and you are not simultaneously testing new material and a new medium. Get three of those out before you decide whether this is for you — the first one always sounds worse to you than it does to anyone else.
If the writing is part of how you win work, the podcast as a client-acquisition channel covers what actually converts. If your material comes out of teaching or research, getting your research out of the lecture hall is the closer fit.