When using the Book Bolt designer, follow these steps in order to add a color to the background of your entire book.
Step 1: Load the designer and log in
First you will want to log in to the designer. You can do this from the upper right hand menu inside of Book Bolt or from the left hand menu under the design tab:
Once you have opened up the designer, choose the cover template, pick a trim size, white paper, and a page count for your book:
Step 2: Add A Shape
The easiest way to add a background color to both the front and back cover of your new book is to go to the shapes menu in the left hand corner.
From there, select a rectangle:
If you click on the shape on your book, you will see that you can select the corners of it. Drag and drop that shape over the entire book until it fills the entire background:
Step 3: Change The Color
Now that you have a shape layer added, it is time to change the color to what you want it to look like.
To do this, simply click on the shape editor in the top menu:
This will allow you to pick a pre selected color, or by clicking into the box, it will open up the color picker where you can customize the color to your liking: