It works just like a tape recorder. If you have a microphone plugged into the "line in" or "microphone" jack on the back of your pc (sound card ports) then you can click on the red dot on Sound Recorder and then speak. Press the square 'stop" button to end it. Then click on "File" then "save as" and save it as a .wav file on your hard drive. Don't forget where you saved it to!
Then all you need to do is attach that file to an email to send it.