That's simple.
just skin dds save as dxt1 format(no transparent)
If you want partitialiy shiny, paint alpha channel white wants area , and save as dxt5 format.
example :
.
HITOMI CASUAL OUTFIT
includes two outfit
-- winter outfit transparent fix, link changed.
download :https://drive.google.com/file/d/0B5jCn51TvJPPb3dPWVRSR3lUWTg/view?usp=sharing