Today, just accidentally, I was starting to think about it again, and discover, that it is not as easy as bashing, but very close.
The first thing was - install Python. In my case I was using Python 2.7.
The second - to set neccessary environmental variables.
And here comes where attention is needed.
In GRASS GIS homepage there are some samples using environmental variables, but it is possible, that user`s machine/computer is differentely configured.
So, here they are:
GISRC= C:\Documents and Settings\user\.grassrc6
1st - Drive letter. In my case it`s D:\
2nd - user. Usually it is the name of user.
3rd - Where the GRASS is stored
4th - Where the Python is stored
5th - What version of Python is used.