So, my recommendation is to not make this a #nostr only business.
1. It's unlikely you'll make a "living wage" in Sats here, but you are early in its use, so set up your territory now. The more you personalize you work here, the better. Utilize the #### to include your name or the signature you go by.
2. Diversity where possible. I'm a member of fb and discord D&D groups. Lots of people create original content for use. Some use AI, some hand draw, dome photoshop. But spreading out to multiple platforms will help you. Maybe even have a Patreon/etc. to link people to. If this is about making enough money to live on, it has to be a full time job with production.
3. If you're looking to build btc in general, consider using the Fold Card (prepaid debit card, look it up or I can send a link) for your day to day purchases.
4. Get into a routine for your posts. Like, say, an item in the morning, an NPC in the afternoon, and an original monster in the evening. Use your original hashtags. Learn how to make D&D stat blocks (for 1 edition or multiple) and put it down as a picture. Pictures catch the eye faster than text, especially on nostr.