Once you sign into your editor's account, the first thing is to take a look at the different sections on your homepage. There is one for Recipes, Layout and Design, Contributors, and Publishing.
The best place to start is by adding a recipe or two. Click on the first link in the Recipe Center and give it a try.
Next invite others to add recipes if you want by inviting them to participate in the Contributor Center.
At any time you can use the Layout and Design Center to select a cookbook cover, recipe layout and other features for your cookbook. Or you can just leave them as is and use the popular default options.
We have a great "How To" Library in the black navigational bar with specific directions on how to do most aspects of making a cookbook.
I hope this helps you get started.