How do you run a T4Toolbox Generator or CSharpTemplate?

I downloaded and installed the T4Toolbox to work with T4 templates more easily... however, I can't even figure out how to run the Generator or CSharpTemplate.

Here is an example file I created:

Template1.tt:

<#+
    public class Template1 : CSharpTemplate
    {
        public override string TransformText()
        {
            base.TransformText();
#>

Hello world

<#+
            return this.GenerationEnvironment.ToString();
        }
    }
#>

I have compiled my application and saved the file, yet no output file(s) are created. :/