Web tickets: When creating the ticket, select the desired tags by clicking on each one you wish to add. The selected tag will highlight in light blue.

To unselect, simply click again.

App tickets:

1. While creating hte ticket, scroll down to the "Add tag" option

2. Select the tag you wish to add and save; or add a new tag by typing it into "New Tag" and add

3. Now your tags will be reflected on the ticket