After creating themes and uploading new CSS data, you may want to use custom images references by your CSS. If you have not already created themes and CSS, please read the following tutorials, How to Create a New Theme and How to Create New CSS. These topics should be understood before proceeding.
Step 1. Locate the Theme to Add Images To
Under the Setup tab, select the Branding node which is located under the Develop category. This will display a list of all themes in the system. Select the theme you would like to add images to. This list will look similar to below.
Step 2. Upload New Images
Under Branding will be the Images node. Select this node to display a list of all images loaded for this theme. If this is a new theme this list will be empty. Select the New button to begin the new image upload wizard. This wizard will look similar to below.
Use the "Choose File" button to select a file from your local system. Once selected you can use the Submit button to save your changes.