How do I start a language on Duolingo?

[Adam2Study]

Is there a way I can start a language on Duolingo and if I can could I make up my own language and use that?

[Woof.]

JaredGriz is right. You can't do that. But if your bilingual in two languages that aren't of your own invention, apply here! https://incubator.duolingo.com/apply

[The_Angry_Mango]

I'm not sure if you can create your own language and put it on here. But I think you can request to add languages if you contact someone like a moderator.

[rumnraisin]

For making a course for your own language, try Memrise or TinyCards or Anki. These are all flashcard apps. I believe full sentences can be put into them all, so a course something similar in idea to Duolingo's courses can be built. If you haven't looked at how to create a language before, then zompist's Language Construction Kit is a good resource.

Duolingo really isn't set up for everyone to start making their own language.

[DaphneTheSnail]

If you are interested in making your own language on Duolingo, I'd recommend TinyCards. It's run by Duolingo and you don't need permission to create it.