In the Resources tab, all available Resources are listed, with their Name and their Color (which is displayed in the Calendar view):
To delete a Resource, simply click the delete button, , in the Actions column.
To edit a Resource, simply click on the applicable row in the list. To create a new Resource, click the Create New Resource button and the following window is opened:
Here, you enter a Name for the Resource as well as the wanted Color, defined by its color hex code. When you click in the color field, the following color palette, where you can select the wanted color, will be opened: