you cant inside a single plugin, since it need to stop itself before starting again (at which point it cant start itself). Chance are tho if you abstract your plugin you can do a "soft" restart, where you restart the logic of your plugin without actually restarting the plugin.
If thats not an option, then youd need a second plugin, that act as a watcher and restart your main plugin if its off. Once thats done you can simply have your main plugin stop itself and your watcher will restart it.