Tip #1 for learning any song is to start with the bass lines, then fill in the rest of the chords. Having some kind of roadmap for the song will help you learn it easier and faster.
Tip #2 is to ignore all the runs and focus in on the main chord changes. So many musicians get distracted by the flair that they lose the simpleness of a song.
Tip #3 is to learn song(s) in their original key(s) first, then branch off to learning it in other keys.
Tip #4 is to not play a song word for word. Every word doesn't need a chord. Music is their to accompany the singing, not necessarily to match it.
Tip #5 is to break the song up in pieces instead of trying to get the whole thing at one time. Once you've learned a piece, practice it until its second nature. Then, add on another piece. After every piece you learn, play the previous pieces with it.
