How To Create a Custom Genesis 8 Character in Daz Studio
Article by RenderHub
This session brings you through setting up essential beginning steps, moving on to face and body morphs. It then guides you through the process of exporting your character to Blender or the software of your choice. Loading morphs, adjusting joints and linking are covered next within Daz Studio.
Setting up these types of product assets for sale is covered in detail. This video will have you ready to not only create custom characters, but also, setup and sell your assets efficiently.
To answer your question... Yes - he has a tutorial right here:
Ion mentions two different sizes because DAZ Studio supports both a small sized one (the 91pixel one) that is what you see in the UI of the program when looking in the Content Library tab, and a larger one (the 256 pixel one) when you scroll the mouse over the icon (what is referred to as a tool tip). He also seems to imply that the better looking icons are created in something like Photoshop or Gimp.