To create a "2nd Skin" you need:

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"2nd Skin" is a program, tha makes Poser Figure.CR2s.  The really interesting part is that when you load a Poser Figure.CR2 into it, the 2nd Skin.exe will output a new Figure.CR2 that is almost indentical to the one you loaded, except that it is a "Skin's" layer thicker.  THe new .CR2 hs allof the same Parts, Joints, and Material Zones as the original.  You then apply whatever Clothing Material you want to it, and touch that off with a Transparency Mask!  Whala, a "2nd Skin."  Very Simple.

What you would need to know how to do is with Photoshop, etc.  You'll need to open the UV Map for whatever figure you want to cloth, and begin the trial and error process of drawing a nice Black/White outlines of clothing.  These will be you Transparency Masks, and define the shape of your clothing.  With a good set of these you can change the fabric/appearance of your clothing over and over!

The Poser Material Room...will allow you to stack/layer materials, with/without Transparency Masks.  In other words you do'nt need to alter(Paint on) a good Skin Texture Map to cloth a figure.  You can comine the two Maps in the Material Room.  Here is what it would look like, and a link to the thread I got into this with:

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2667893

Since then I've become more adept at this.  Attached is an image of a Alpha/Suit I did for a client, with just photoshop and the Material Room.  This character is known as Rebelette, by Mike Shoemaker(Rebelette.com)

To really get an idea of how powerful the Material Room is, checkout this link!  Mind you this image wa rendered with only V3's skin Material Zones.  There is no clothing geometry added, I just used the Transparency Mask I'd developed, and bagginsbill's Matmatic Chainmail material!

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2694524&page=1