Jeff makes several Great points here about Regions,  Comments, Threading, Refactoring and Naming conventions.

We don’t always practice them all here, but strive to do better.  Most of our Code Generation templates do output code that is very descriptive and readable even if we don’t expect people to read the code, the Philosophy is along the lines of “but what if we need to during debugging or something…”  Having clear and concise coding guidelines makes that task much easier.  Describing what something is supposed to accomplish in the comments has been an essential practice for a long time, code no longer describes itself when you are not writing monolithic apps, even then it was a sure challenge just to find things.

Great custom control development is a skill that takes more than time and experience to perfect. It’s also not a widely documented practice. When it comes to Silverlight controls, there are similarities and differences from WPF custom control development, too – so that chapter on controls in your favorite WPF book often is not directly applicable.

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I do admit that there’s a lot of flexibility in control development, so I’ll be basing a lot of my tips on both official and unofficial practices on the Silverlight Toolkit team. And I understand if you don’t agree with everything I have to say. But I do hope this information will be useful!

Jeff Wilcox – Custom Control Development: Simple code guidelines