I tried the "traditional" way until I accumulated 50 rejection notices. Then I turned to self-publishing. I put two books out on Amazon using their Kindle Direct Publishing (KDP). It's free to sign up with and practically painless. They give you software to download, called Kindle Create that helps you format your book the way you want it. Add pictures, chapter delineation, numbering, and all that. Then click "Publish." Amazon does the rest. You get a free ISBN number, plus your novel is available around 24 hours later. The paperback option take a couple of days.From first loading my novel into KC to seeing it on an Amazon page was around 36 hours.
They only require you give them a bank account (I made mine a secondary account to my savings account) so they can put royalties into it. If you go over $100 a year in royalties, you'll get a tax notice for when you file as well.
Bill