Download audacity, if you don't already have it. Follow the installation instructions on you screen. Also download a plug-in called LAME if you would like to export your final product as an MP3 file.
Open Audacity and record or import the media you would like to enter the metadata about. Click on the word "File" at the top and them select "Open Metadata Editor." This will open a screen with information you need to fill in.
Fill in the metadata information such as the name, title and Album (if any). You can also fill in the genre (type), track number and any comments you might have. Select "Save."
Select "Export," and this will automatically open the metadata window if it has not been filled out before. This can also be used if you have imported a file and made changes that you want to keep separate from the other file: for example, if you put a voice over some music and don't want to save the file by the same name. Once all the information is filled in you are done.