In this 42 page THiNC book you'll find a discussion of Texture vs Prim clothing. (Only Texture clothing is covered in this book.) You'll also find out what, exactly, a Mesh is, and how that relates to UV Maps. What UV Maps are, and why anything you put on one arm (or foot) shows up mirrored on the other. What "gotcha"s you need to know about when drawing on the UV Maps, so you can avoid them.
You'll learn about Clothing Layers; what is rendered on top of what, and how much of the AV each one covers.
You'll also learn the best method to design clothing using the UV Suit (included in the book) and how (and why) to test your clothes before you spend much time on them. How to test things for free on the Beta (Preview) grid, along with detailed instructions on how to get in there. And what parts of the Avatar always cause problems, and how to avoid them.
Finally, as a bonus, there's a short discussion about using tileable patterns as fabric, including how to make Patterns in Photoshop.
You can read it all for free, in the Texture Library at Livingtree (113, 97, 25).
If you decide that you like it enough that you want to have a copy to take home with you, you can get one for only L$100. That's just 10 uploads, so the book will pay for itself over and over!
If you can click on links in here, that's The Texture Library to read the book, or to buy a copy.
See you there!