Hi. This is a tutorial of how to install a new theme into your phpBB forum

Step 1

Download the theme you want to install to any location in your computer

Step 2a

Open your FTP program. If you don't have one then proceed to step 2b.
Login to your FTP and go to your forums root folder.
Open the map templates and upload the whole map of the new theme into the map /templates with all contents.
The result will be this: /templates/new_theme/

Step 2b
Login to cPanel en go to the file manager
Click on the directory icon next to the directories "public_html" or "www".
now. go to your forums root folder and go to the templates directory. Make a new directory with the name of the new style. And create two new directories under the map of the new theme.
Name the two dir's "admin" and "images" and upload all desired files to the right location.

Step 3
Now that you uploaded everything: Go to your forum and go to the administation Panel. Once in. Scroll the left page down until you see styles. Under it, click on add. There should show a page up. You will see the new theme here. Click on Install that is next to it. Now. It should be installed.

NOTE: Only read further if you want the new theme to be the default.

Step 4
Now. Go to your forums configuration page. Then o to default theme and choose the new theme. Now. Scroll further down and click on OK.

Now you are done and have a new theme installed. You can install as many themes as your diskquota remains.

I hope you could use this tutorial.

Glad to help.

Have a nice day.