First you need
SimPE (Simple Package Editor):
http://sims.ambertation.de/And Microsoft .NET framework 1.1 and 2.0 from Microsoft Update (depends on the version of SimPE, but having both hurts nothing)
And
nVidia DDS Utilities from here:
http://developer.nvidia.com/object/dds_utilities.html------------------------------------------------------------------------
Then in SimPE - look for EXTRA at the top, then select PREFERENCES

In the System Folder section - Set the Nvidia DDS Tool folder:
C:\Program Files\NVIDIA Corporation\NVIDIA DDS Utilities(or D: or E: where ever it was installed) -- the rest you will best be
served by default
Click OK
Exit SimPE and you are ready to begin.
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Now make your skintone in BodyShop, or more appropriately Booby Trap.
Close Body Shop.
Now with Photoshop or Paint Shop Pro or what ever graphics programme you
use, save each texture as a PNG (24 bit)
Open up the Skintone you just made with SimPE
Scroll down to the Textures in the directory tree on the left side of
the panel.
Now, select the textures one at a time and do the following.
When you see the texture in the preview pane, right click and
Build DXT...
Change the
Sharpen option to "
None"

Now open Image and browse to the appropriate replacement PNG

You will see a DOS/Command window pop open and "compress" the image.
Click
Commit and save the file after each replacement.
Repeat as necessary.
Note: DXT3 is a better format because it does not compress the image nearly as much, but may not work in Mac versions of the game. My tests show it works perfectly well for the PC version.