1. Go the traditional publishing route
The big benefit of going the literary agent/ traditional publishing house route is that everything (except marketing) is done for you. You get an editor and a copyeditor. Your book’s cover and formatting are done for you, as are paper editions, and audio editions.
The only hassle with traditional publishing is that it takes forever. It might take a year or longer to get an agent, then another couple of years to sell the book to a publisher, and get published.
The drawback of course is that you make much less money. If your novel doesn’t hit any bestseller lists, it’s unlikely you’ll earn out your advance.