Research is everything.
You need do your homework before you self-publish your book. Weigh up if that’s really the route you want to take. Explore what stories other writers are writing, find out who would be interested in your story.
These tips are from a 2016 video series I filmed after self-publishing a children’s book in Australia. Find all 20 videos on TAKU TV at https://www.youtube.com/playlist?list=PLc-QE_S9GwVCh40ZavHMT39zvwVnosazY. (Tips start at 2:00 in the podcast episodes).