Attributes work in conjunction with styles.   A style is a grouping of items that have virtually the same characteristics but differ by their attributes.   For example a shirt can come in different sizes and colors where by color and size are attributes.  Within each attribute are 'Attribute Selections'.  Here you would list all potential variations in color or size.   

To create a new or edit an existing attribute,  click Lists --> Profile Lists --> Attributes.   Enter a unique name for the attribute then add your attribute selections by clicking on an open line of the grid in the 'Selection' column.  Enter a unique name and abbreviation (within the attribute).  Repeat until all your attributes and selections are entered then click Save, Save & New or Save & Close.  You can add an unlimited number of attributes and selections.