I've been self-publishing my novels for years, and using an EPUB editor is a game-changer. My go-to is Calibre—it's free, user-friendly, and packed with features. After writing my manuscript in a word processor, I convert it to EPUB using Calibre. The editor lets me tweak formatting, fix metadata, and even embed fonts for a polished look. I always preview the file on different devices to ensure compatibility. For covers, I use GIMP or Canva, then add them via the editor. Once everything’s perfect, I upload the EPUB to platforms like Amazon KDP or Draft2Digital. It’s a straightforward process once you get the hang of it, and the control over the final product is worth the effort.