Install the extension from the Visual Studio Marketplace or in the in-app Extensions manager.

Close Visual Studio and follow the prompts to modify your installation.

Get your User ID (and optionally Team ID) from the Visual Studio extension page.

Open the Refraction Settings in Visual Studio

Enter your User ID and optionally Team ID.

Close the Setting window to start using the extension.

Open a file in Visual Studio.

Select some code.

Select Tools > Refraction

Select the command you want to run e.g. "Generate unit tests"

Refraction will generate the code and insert it into your file.