When you purchased the plugin you should have got an email with a download link.
Install the plugin in the normal way as plugin. Plugins > add Plugin > Upload and upload the zip file, then activate the plugin.
Once activated the plugin will request your licence key, also provided by email.
After activating your licence, the settings page will be display, the plugin will already be operating with the default settings.
If the status box is showing ‘not fully operational’ in the first instance, try simply saving the settings. If it continues to show not fully operational then refer to this article.
You can adjust the configuration as required by your specific needs, configuration details are available through the help descriptions on the settings page with more details in this section here.