First, go on the internet and search for the song's lyrics. Remember, if you want it to works properly, you need to find two types of lyrics: the normal text one, and synchronized one which is found in .lrc file types.
The first normal text ones are easy to find through famous sites such as metrolyrics or azlyrics,etc..
The .lrc files are a bit harder looking up and not always available on the internet. You could learn how to make one yourself right here
If you know any good sites that share this type of lyrics, please share
Second, create a notepad and paste the normal lyrics that you found to there, save the file without any extension, name it Songfilename_lyric.
In the same way, copy the content of the synchronized lyrics to notepad, save the file without any extension, name it Songfilename_lrc (LRC not IRC)
For example, If your song file name is ABC.mp3, name the files ABC_lyric and ABC_lrc
Third, plug the phone into your computer, copy two files that you've created to
Computer\HTC One X\Internal storage\Android\data\com.htc.musicenhancer\files\.albumarts\storage_external\Music
Remember, look for a file name Songfilename_not_available in that directory, if it exists, delete it
Enjoy
Note:
The _lrc file is required for the lyrics to pop up while you're playing music, if you don't want it, then you don't have to create
Try to google search "filetype:lrc Song Name" if you don't find any synchronized lyrics with normal searching
If you have any questions, leave a comment
I will try to add Screenshots as soon as possible