Welcome to the Wincustomize and Stardock Community!
First, make sure to download SkinStudio11 from your available software here:
https://store.stardock.com/myaccount/products
In the Object Desktop tab, click on Product Downloads and you should get a list of software.
Then, take the Diamond skin that comes with WindowBlinds11 and see how a skin is made up. You can also download a skin, rename .wba to .zip and double click on it to simply see all the files ans images, etc.
Make friends with a good teacher like basj or Lightstar - there are many great folks here who can help guide you.
You can also post questions in the appropriate forum/subforum.
In any case, welcome to you justindev!