Handbook translation

[Ganbold]

Hi,

I and my other colleagues are thinking to work on Mongolian translation 
of FreeBSD handbook.
So in this regard we have some questions:
What is the correct way to begin translation of FreeBSD handbook to 
other languages?
Are there any steps? Is there any docs/references which explains this?
Which is preferable method? To work on clear text or work with sgml files?

I appreciate if somebody can give us some advices and recommendations.

thanks in advance,

Ganbold