How can I run the game?

To get the game up and running you need to install "supybot" from your distributions packages.
Then create an empty directory, and change into this directory. Create a folder called "plugins" in the newly created folder.
Now download the latest release of "supybot-werewolf" from the Launchpad homepage. Put the release tarball into the "plugins" folder and unpack it.
Now change to your newly created folder (which should only contain "plugins") and run supybot-wizard.
The supybot wizard will ask you several questions. Give him all the information he wants. Generally you can just leave the defaults. When you're reaching the step "Would you like to look at plugins individually? [y/n]" enter "y" and enable the Werewolf plugin by typing "Werewolf". It will then ask you "Would you like to load this plugin? [y/n] (default: y)", which you want of course!
You're done and can run the game with "supybot nick_of_your_bot.conf" now!