There are three ways you can apply a tag to a property:

Property Wizard

Tags can be applied as you are creating a new property through the property wizard.  The Details section on first screen of the property wizard contains a tags field.  Enter one or more letters to view any matching existing tags.  If the tag you are after doesn't exist, continue typing to create and apply a new tag.

Once the property is created, the applied tags are visible on the Properties screen.

Import a Property

When importing a new property, a column has been included to add tags to each property.  Enter all tags for each property in the Tags column, separating each tag with a comma.

Property Details

Tags can also be applied or removed to existing properties from the Property Details screen.