Make a list of people you want to thank. Be as thorough as possible so you don't risk forgetting anyone. You can edit the list later; but, for now, capture everyone you can think of. Don't forget to include those who encouraged you and offered moral support. Acknowledgments typically include parents, supportive friends, mentors, editors, cover designers, illustrators and professional sources who helped make the novel more credible.
Type your acknowledgment thanking all those you wish to recognize. This is not merely a list of names. Include specific ways each person assisted you with writing your novel. If you need help writing it, read several acknowledgment pages in other books to see how they are formatted and how they are worded. Write your own using these as a guide.
Edit the acknowledgment section to about one page so readers will not lose interest. Limit the list to those who were particularly supportive and add a sentence thanking everyone else. If you have many people to thank, be creative in your editing and limit your words. If you can't do this, ask someone else tp edit and condense it.
Include the acknowledgment page in your novel. It is typically placed in the front, after the copyright page or after the table of contents. The location is not set in stone. Some novels place the acknowledgment page in the back of the book, before the "about the author" page. The choice is up to you, unless you are being published traditionally. In that case, your publisher makes the decision.