Write the book or develop a written proposal for the book you want to develop. Not all publishers require a finished manuscript, but you must at least have a concrete proposal to offer.
Hire a literary agent to help shop your book around to publishers of textbooks and educational literature. Most major publishing houses will not accept unsolicited manuscripts; therefore, having an agent gives you the in-road to getting published.
Locate, via the agent, publishers who are interested in your book. The agent will also help negotiate terms of the contract if you and the publisher can arrive at an agreement.
Guide your book through the rest of the publishing process. You will finish writing it if it's incomplete or revise the book based on the review of your editor who works for the publisher. Your editor may require additional material, research or fact-checking.
Develop a marketing strategy. Although this is traditionally the responsibility of the publisher, writers are increasingly expected to assist with the marketing of a new book.