Buy block ISBN numbers from Bowkers if you want to sell through commercial channels.
Use Lyx to typeset.
Design or have a designer design covers.
Run to Createspace. Pro Plan costs $35.00/year. You buy proof copies (Proofs of my 200 page novel, Freein' Pancho, cost $3.85 plus shipping), when you release, they place in Amazon, Ingrams and other distributors.
You market (hardest part).