Summarize the following:
If you want, you may hum or sing it in your head, just so that you can get the song in your head. Repeat until you have mastered the song and you can play the song back in your head.
Pick a song you want to play and learn the lyrics. Play the recording of the song back to you and sing along. Pick up the guitar and play along with the recording, but only guitar. Once you master the song and you can play it without looking, start humming, or singing out loud while playing.