Think about who the main character is – maybe it can be an adventure of a toy somewhere?
Write the story and draw a storyboard to plan how your book will look.
Take photos or create graphics for the pages.
Use the vector editor in aviary.com to alter your text to make it more fun.
Use Blurb.com software to create your book and get an online version of your book that can put onto a website or blog. You could even buy your book to get a copy you can read to any young children you know.