Question create my own customization of WM6

Hi,

I see a lot of people to customize (color, applications, and so on...) WM5 or WM6.

I would like to know how it is done. Which software or tool do they use, does it exist a tutorial for that, and so on...

In fact our company bought more than 60 SPV M3100 (Hermes 100) and i would like to make a company package (WM6 customized) for that purpose.

thanks a lot for your help.
Maileen