Creating

In order to use tags, you need to first create a set of tags which you wish to use. There are three main methods to create tags.

Method One:

Select Tags ▸ Create New Tag....
Select a parent tag for the new tag to appear under, such as people or events. If you wish to create a new tag without a parent, select (None).
Name the tag.
Click Create

Method Two:

In the tags page, right click, and select Create New Tag...
Select a parent tag for the new tag to appear under, such as people or events. If you wish to create a new tag without a parent, select (None).
Name the tag.
Click Create

Method three has the advantage of also attaching the new tag to the photos selected. To do this:

Select the photos to which you wish to attach the new tag.
Right-click on the photos, and select Attach Tag ▸ Create New Tag....
Select a parent tag for the new tag to appear under, such as people or events. If you wish to create a new tag without a parent, select (None).
Name the tag.
Click Create