There are two places where you can create tags: the store/ directory and the tags/ directory.
The tags/ directory is the recommended place to manage your tags. You can create them, rename them and delete them too. But the tags/ directory does not allow you to tag your files. This role is assigned to the store/ directory. There you can create and delete tags too, but you can also tag files by copying them inside one or more tags, but is not advisable to use the store/ directory do delete tags. We'll return on this and on the tags/ directory later. So far just assume you'll be using the store/ directory only.
In respect to an ordinary directory, the store/ directory is something completely new. Be prepared to learn something before using it. Inside store/ the assumption that two directories can't be parent of the other at the same time falls. But let's start from the most simple operation: creating a tag. Remember that in Tagsistant a tag is just a directory created right under the store/ or tags/ directories. Knowing this, all we have to do is to use mkdir:
$ mkdir ~/myfiles/store/video/
$ mkdir ~/myfiles/store/scifi/
$ mkdir ~/myfiles/store/startrek
What we have done here can be translated in English as: create a tag called video, a tag called scifi, and a tag called startrek.
To understand the binding between store/ and tags/, list the contents of tags/ and you'll find the tags you've just created under store/:
$ ls ~/myfiles/tags/
video scifi startrek