WordPress.org

1. Unzip calgraph.zip in /wp-content/plugins/ directory
2. Activate the plugin through the 'Plugins' menu in WordPress
3. Check /wp-content/uploads/ exists and is writeable by webserver (permissions of 755 sufficient if owned by webserver user)
4. Requires php-image-graph, php-image-canvas, php-gd, php-pear, Image_Color installed (See below).

To Install Requirements:

On OS like Ubuntu:

# apt-get install php-image-graph php-image-canvas (Will also install php-pear and php-gd as dependencies)

# pear install Image_Color