To install a phpBB template you should have a phpBB2 board system installed on your server. Download it from www.phpbb.com if you don’t have one. The installation process is quite simple. Decompress the phpBB archive to a local directory on your system and navigate to the “/docs/” folder the “readme.html” and the “install.html” files, these files will walk you through the basics on installing the forum software.
When you have a phpBB board system installed, unpack the template package. There will be a folder named “Forum_XXXX” (where XXXX – is a four digit number). This is a phpBB theme. Place the files in their own directory (“Forum_XXXX”) in the “templates” directory inside your phpBB directory. If your server is online somewhere, then you’ll first need to unpack to a directory, and then upload it to your server. Do not rename “Forum_XXXX” directory.
Go to your administration control panel.
Under “Styles Admin”, click on the link “Add” you will find a list of styles that are present in the “templates” directory but that haven’t been installed to your forum. Behind every style, you see an “Install” link. Click on that link to install the style.
If you’ve done this for all the styles that you wanted to install, then have fun! They’re now available to your users, or to you to set as the default style in “General Admin > Configuration”.