Filters are keywords that you can attach to files to allow you to sort and search through them more efficiently.

Navigate the to template you'd wish to add a filter to by going through the Setup drop-down, and selecting the type of template for which you are looking. 

To change the name of the file or add a filter to an image or document, select the file and then click on edit.

Click on the "More" drop-down menu, and then select "Info".  To add a filter, type the name into the filter bar, and then click on the drop down menu. If a filter is already created, it will appear in the drop-down after the first option and you will be able to click on it and select it. (Note that you can add multiple filters to each file). Alternatively, you can select a Search filter tag under the "Filter Category" heading by clicking on its corresponding checkbox. When you have made your selections, click "Save".