Proofread your book. Correct any typos, grammatical errors and rewrite any unclear passages. Get someone else to read it and look for the same problems.
Join a group like the Erotica Readers and Writers Association. Here, you can have your book critiqued chapter by chapter to make the story the best it can be.
Sign up for the Calls for Submissions from the Erotica Readers and Writers Association. This email will alert you when publishers are looking for books and stories to publish.
Follow submission guidelines carefully. Submit only what the publisher asks for; anything less or more could cause rejection without reading your book.
Read any contract you may receive carefully. Fully understand what you are signing. While seeing your name in print is very exciting, giving away your rights could leave you with a very bad experience in the publishing world.