Creating a custom SmartTheme is simple: you just create a site, under your Design Partner master account, that is exactly what you want the SmartTheme to be. Then, when you have it just how you want it, go to your master site, view the list of sites (Settings > My Sites), hover over the row for the site you want to use, and click at Create SmartTheme (compress) icon to the right.
You'll then see a form that asks for information about the SmartTheme and allows you to choose some options. Here's some notes on each of the fields:
The settings listed above provide cataloging information for your custom SmartTheme, but they don't affect the SmartTheme itself. The last two settings do, however, and it critical that you understand what they do and use them appropriately.
If the directory you specify has subdirectories that you also want to include, you may include the suffix "**" at the end of the directory name to have the system automatically include all of its subdirectories. If your "/images" directory also has subdirectories of "/images/icons" and "/images/badges", you can include all of these by writing "/images**". If you want to include ALL files in the account, use "/**".
A SmartTheme includes, by default, the content of your database, as well as its structure. Often, you may want to disable this feature. For example, if you have built a business database SmartTheme, you're likely to fill the database with content to confirm that everything is working as you'd like. Then, when you create a SmartTheme, you'd like to leave all this data behind. To do so, just uncheck the box labeled "Include Database Export."
SmartThemes are intended to be able to represent any Webvanta site design and data structure, along with modest amounts of data. The system currently has the following limits; if any of them are exceeded, you will not be able to create a SmartTheme:
Using SmartThemes to Simplify New Site Creation provides a summary of how to use SmartThemes.
Editing SmartThemes Offline. Details on the SmartTheme file format. This information is needed only if you are editing SmartThemes offline.