1. Download AutoMOD from http://www.phpbb.com/mods/automod/
2. Upload it to your phpbb root folder by your favorite tool.
3. Unzip automod-1001.zip file in the phpbb roof folder
4. Copy and overwrite the the unzipped folders on root directory as shown below.
5. Copy all the folders inside this/uploadfolder and overwrite it on the root directory of phpbb.
Below comment will copy only the new files and leave all the existing files.
( Or ) you can unzip it in your local system and directly copy from your local system to phpbb root ( you can use your own method to copy these folders).
6. Now go to http://yoursite.com/install
example – http://forum.melbia.com/install/
and follow the instructions
Once the installation is completed remove the install folder.
Now you can use this plugin for install / Uninstall phpBB Modules (Modifications) .