In this example I will create the anthem of Japan but you can do it for any other National Team.

You can download the anthem in mp3 format from this site.  In FIFA all the anthems have a duration ifrom 26 to 29 seconds. Open the file with Audacity and cut part of the anthem to fit the required duration, typically a good choice is to keep the last part of the anthem.

To add reverber makes the sound more similar to a stadium execution but you can skip this step, select all the sound and click Effect- Gverb. 

 Now save the edited sound clicking File – Export as WAV ang give a name, for example, Japan.wav. Close Audacity.

Launch SM and Open Chants

Import the chant clicking the “Import Chant from WAV” button and select the file.

Create a new reference,

Select the reference and edit its fields as shown below.

Thats's all. Save SM and exit.