The biggest video sharing platform of the world, who don’t know it?
If you have some video creating skills, try creating a video to advertise your server.
Make the world know your server by creating a good video that tells everyone what they can do in your server.
You can also make explanation-videos for plugins, coding, tricks or something else and point to your server somewhere in your video.
You don’t have to do this by yourself. You can ask someone to help you or even convince someone to do it for you. In that way, your server will pop up when someone is searching for a good (new) server to join.
You can even make some money with your videos when they get popular.
It’s always handy to enable Google Analytics/Ads for your videos. In that way, commercials will be played before your server start and some revenue will be added to your YouTube account.