What is the best way for an author to create a book in the .epub format?

Hello,

I have been wanting to start making some of the short stories I write sometimes into books. While going through the app store, I found iBooks Author but there are many unlabeled buttons and the interface is very strange, along with the fact that it doesn't read out as you're typing.
I've never used any files other than what was sent to me or basic text formats, but if I were to sell my books on iBooks, Google Play, and/or Kindle, it would be easiest to just have one copy of the book, an .epub file.
I know basically nothing about the file type, but it's the easiest way to publish on multiple sites.
So, as the subject says, what's the best way to go about creating them, from scratch, for an author using the Mac? I don't know if it would be best to pre-write and convert, but then I worry about it not formatting correctly and being uneducable, or something like that.
I really appreciate any help any of you can give me.

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#1 Pages

I use Pages to make epub books sometimes. I'm doing it on IOS, but it looks like it's much the same on the Mac, from what I've read.
If you set your document up with titles and headings, it makes a table of contents for your book. It sounds like you're making short stories, though, and you might not need more than a title.

#2 epub format

Hi, Taylor. Actually, most publishing platforms, such as those you mention, have their own formatters. 1 of the most wonderful inventions in a long time is, IMO, a language called Markdown, or 1 of its variants, that allows a writer to format their text very quickly w/headings, etc. For example, a level 1 heading might look like:
#heading 1#
2 hash marks precede & follow a heading level 2, etc. Bulleted lists are made by preceding each entry w/a * star), bold can be done by preceding & following the text w/*'s, ie, *this is bold text*, hyphens for underlines, blank lines for paragraphing, etc. Using Pandoc or similar, Markdown can easily be converted into a variety of formats.

You'll just need to see which variant you prefer, ie, markdown, textile, CommonMark, etc. It truly makes document formatting a breeze, & you don't have to screw w/all the operations word processors require, ie, select text, go to the formatting menu, find the style, etc.

I'm a hobbyist writer myself, & I truly do love markdown!

#3 pub

Pages will save your document as an ePub. You need headings and sub headings, and so forth.