Start at the point where they didn't have a language, to how they got one, how it has changed them.
Who - Mayans - Their importance?
What - Mayans & Languages - What lead to development, effects of the language?
When - What time period? How did having this language or a language differ them from other existing civilizations?
Why - Why did they need this system?
How - What lead to the creation?
I'm assuming you're talking more than just the language of the mayans because that's far too vague, it's not easy for a language to change, etc, perhaps from roots. Ex, Latin.