If you have written a children story book and already self published or planning to self publish, then there are a few things which you must consider. One of the aspects is to have an online presence of the book. The more the online presence, the better for the book.
Having an E-book can be an answer to many questions, and if your E-book is present on Amazon and other online book selling websites , then you just increase your chances to be seen by a lot of audience. As far as the promotion of printed books is concerned, you can definitely make use of your networking and promote it in schools,libraries and other places where it can sell.
Having a website where you write about your book, or put It for sale can be very beneficial, and also you can put the Amazon link where your audience can go and buy the book. You can optimize your website on keywords like Children book, or the topic which you are writing about. For example, if you are writing on child abuse, just optimize your website for the keyword like, latest children book on child abuse. So, when there is a parent searching about child abuse on Google, your website will be shown on top. This way, you can be seen as a children book author as well as an author writing on a particular topic.
By promoting your book online, you actually become available to unlimited number of people who may be interested in what you are writing. As a children book writer, you must tell the world that you are there and writing on such and such topic.
You can hire a good website designer and also request the same agency to optimize your website for keywords which you think will help you reach your target audience.