You may have previous experience using TestDriven.NET with another test framework such as NUnit. The experience with Fixie is exactly the same.
TestDriven.NET is a third-party plugin for Visual Studio which allows you to run tests within the IDE for tests written for a number of different test frameworks. It is free for students, open source developers, and trial users. Companies, organizations or other individual developers can purchase the plugin for a reasonable fee.
TestDriven.NET can be set up to run tests from your whole solution, an individual test project, a single namespace, a single class, or a single test method, all depending on where you are focused in the IDE when you invoke it.
Install the third-party TestDriven.NET plugin into Visual Studio, install Fixie into your solution via NuGet, and then run tests using the same context menus and keyboard shortcuts you would use to run your NUnit tests. Results and console output are directed to the Visual Studio Output window, and you can double-click on test failures in that window to navigate to the offending tests.