Folder Menu Vertical is a flash dynamic menu module for your WordPress 3.0+ website, designed to meet your needs and preferences.
After downloading the ZIP file
1. Login to your WordPress site and head over the 'Plugins' menu
2. Click 'Add New'
3. Choose the 'Upload' option
4. Upload the downloaded ZIP file.
5. Once it is complete, activate the plugin.
Once the plugin is activated, you'll notice a menu on the left called "Folder Menu". Here you can select the menu from the list of your WordPress menus, and also change various parameters.