If you don't have a /my-plugins/ directory in your bbpress installaltion, create it on the same level as config.php.
Upload the file into /my-plugins/ directory
Also copy the PNG images into the my-plugins directory. There is an alternative icon for the "no" status which is orange instead of red, rename as required.
If you are migrating from version 1.0 of the plugin, go to the administration area and update the topics to the new format
Configuration can be carried out within the admin area of bbPress, you will need to be logged in as a keymaster.