Target your market. While many parents read picture books to children as young as 1 year old, the typical picture book should be aimed at children between the ages of 3 and 6. This means using characters and situations that this age group can identify with. Characters can be human, animal or even inanimate objects (though human characteristics are often given to the latter two) and typical themes range from making new friends to sharing. Whatever the topic, plan on much of the story being delivered through your illustrations.
Write the text for your manuscript in a word processor, independent of illustrations. For picture books, the text per page is rarely more than a paragraph consisting of three to five lines. Text in a picture book should be simple. Format the text in block paragraph style, with each block representing a page.
Indicate the illustration that will accompany the text. There is one illustration per block of text, since the illustration is used to convey the storyline. Follow each text block with a parenthetical. The text within the parenthetical should direct the reader (an editor) to the illustration that will accompany the text. Example: (Illus. 1). Be sure that each of your illustrations is labeled accordingly.
Submit your picture book manuscript according to individual publisher guidelines, if you have them. If no specific guidelines have been given, submit your manuscript and illustrations together. Include the text manuscript and a hard copy of each marked illustration. If a publisher uses an in-house illustrator, as many do, do not include your own illustrations with your manuscript. Write a note to suggest illustrations and submit it with your manuscript.