very easy i will make you a short tutorial with the basics
Tools:
Image editor: anything that can save a file as pcx (i will be using Adobe Photoshop CS FYI: normal texture size is 256x256)
UTSM: v2.4.1, v2.5 beta 6
Free Downloads:
http://oldapps.com/Paint_Shop_Pro.php
http://oldapps.com/old_version_PainDotNet.php
http://www.acordero.org/prog_proj_UTSM_Download.html
Step 1:
Open UTSM
Select File>New Project
Select a Model
Save the file
Rigth Click > New Skin
Save name your skin similar to this
If you need a file to work from Open UnrealED
Open Texture Browser
> Browse for File 
Select the soldierSkins.utx For example I am selecting one of ym previous skins
Right Click on skin file (You will need a Chest, Legs, Face, Arms, and Talk Texture) > Export to PCX
Make sure the file is changed from Indexed so you can edit the texture (Change it back before saving or you will get a raindbow fuzzy picture)
Save the file as PCX
Im UTSM Right click > Add Texture > Select File
After you fufill all of the textures for each color the savign process is as follows
File > Save As
Then To Install Click actions and Compile
And your done!
