1. Get a domain name the same name as your book. (If you want to – can sell from the web page)
2. Start getting your cover (and back) designed. For ease you can find someone in Fiverr (www.fiverr.com) or Upwork (www.upwork.com) or People per hour (www.peopleperhour.com)
One will be for a PDF then get the other one edited for a printable book.