Now I already have the theme downloaded in my themes section, but this is how you are going to do it. on that page, go to install theme,

Once you get to that page you are going to see some stuff. First you will see a search bar. You can search for your theme. When you scroll down, you can search by checking off what kind of theme you are looking for, but I wouldn't bother with that. Just go to the search bar and type in Xena store.

On the next page, You are going to see how to download and install the theme.