WordPress.org

1. Upload the entire /dfe_news_harvester folder to the /wp-content/plugins/ directory. You can exclude the /wp-admin folder.
2. Activate the plugin through the 'Plugins' menu in WordPress
3. Begin registering feeds and setting up configuration in the plugin's menu pages.
4. Optionally, install the "harvest_this.php" file into the /wp-amin folder

Upgrading from 0.5: you'll need to actually physically copy the "harvest-this.php" file to the correct location, /wp-admin, in order for it to work.