The resources I collected for this challenge are by no means complete and should therefore only be seen as some kind of "starter kit".
In case you stumble upon websites, books or other things for your challenge language, and think that they would help other challengers in the future, please do not hesitate to send me a link to whatever you found. I will gladly add it to the resource list for future challenges. (Just text me on Twitter, Instagram or mail me.)
If you don't want to study alone - or search for resources all by yourself - check out the Connect page!
Below are some websites that span a wide range of different languages. If you have no idea where to start or want to get a first impression about your challenge language, you might find some inspiration (and resources) there.
Omniglot: "The online encyclopedia of writing systems & languages". You should definitely check it out, the author Simon Ager did an amazing job in collecting all kinds of different resources for a huge number of languages.
Live Lingua Project: "The World's Largest Repository of Free Language Learning Material". They offer material and courses for a variety of languages.
Learn101: Language collection with basic grammar and vocabulary material for each language, often with audio files.
You have never studied a language from scratch on your own before? Or you just don't know what to do and where to start? Maybe one of the things below can help you out.
There are a lot of places both offline and online, where you can find study material. Visit your local library or a bookstore; check out the app store or search around a bit on the interwebs.
Get into different resources you found before tying yourself down on the first you stumble upon. Often you will find small treasures when you don't turn down a resource after just a minute.
Like LingQ, Memrise, Mango, Duolingo, etc.
This could be something like: "I want to learn Cyrillic over the weekend" or "I want to introduce myself". It shouldn't be too big a goal, since the challenge spans only three days, but everything that motivates you to sit down and study will do.
Learn how the syntax of your challenge language works. Find out how verbs function. How do you build a question? What are the grammatical differences between your challenge and your native langauge?
Listen to slow news. Search for an interesting podcast. Watch kid's TV. Read lyrics while listening to music. Search for subbed movies/series.