Download your current Attributes File and add a new column
You can navigate to the Samples section to view your current attributes and re-download that attribute file. Once an attribute is uploaded, it cannot be removed from the experiment, but you can add new ones by inserting a new column into the existing attributes file. After adding your desired attributes in new columns and saving the file, click "Add Attribute" to upload the updated file. You will then see those additional attributes appear here and they can be used to set up new Comparisons. For more information on how to upload an Attribute File, see here.