First of all there are a couple of mistakes that beginners like to make really often. They're listet here - with solution of course ;-)
(1) Patch 1.04 is not installed
It's basic assumption to bring your installed Darkstone-Version to 1.04 or higher, so you can use custom skins. I reccomend everyone to patch to the latest version (that is 1.05b).
(2) Wrong Directory-Names
There has to be a skin-directory in the darkstone-folder. It has to be named "skin" - case sensitive (not Skin, skins, ...).
(3) Naming-Conventions of the Skin-Files
The Files have to be named charactername.tga and for the face charactername_face.tga. Your Windows-OS may not display the correct file-extensions if you didn't customize your explorer-options - so be careful that the file isn't named charactername.tga.tga.
If Darkstone isn't able to load the skin-file it takes the default-skin. If the skin-file exists but is corrupt the character is shown as a white ghost.
(4) The file is there, the skin is completely white - why?
The white ghosts usually appear when the format of the skin-file is wrong. It has to bee an 24-bit UNCOMPRESSED Targa-Bitmap.
(5) The textures are really weird
If the textures don't fit to the character-model you're using a wrong type of skin. Pay attention to the fact, that an amazon-skin can only be used with an amazon-model - so for instance it should not be used for a monk-character!