Lips

To get this medal you need to maintain the correct pitch for the duration of a note. When you sing a note in the right pitch the bar for that note fills with colour. If you can fill that bar from start to finish with colour for a majority of the notes in a song then you should get this medal. You'll need to be awarded this medal 30 times to get the achievement. You can speed the process up a bit by playing 'Vs' and singing in to 2 mics at once.