creating/appending to the userSetup in general is a sinch.
first check if you already have one (it should be in one of you maya/scripts directories - either in Documents/maya/scripts or Documents/maya/<version number>/scripts or finally Documents/maya/<version number>/prefs/scripts)
1-
If you do have one, open it up in a text editor (notepad etc) and paste in the given line of code at the end.
Then save.
2-
If you dont then open a text editor (like notepad), paste in the given line of code.
Save As "userSetup.mel" into one of the above script folders - I personally prefer "Documents/maya/<version number>/scripts".
(under save as type say "All files" to use your ".mel" extension).
I hope that helps.
