Enjoy. NB - This also works well on the flute. 


  G  G  A    G   C  B      G G   A    G   D  C
  Happy Birthday to you,   Happy Birthday to you,
|------------------------|------------------------|
|-------------------0----|------------------------|
|-0-0---2----0---0-------|-0-0---2----0---2--0----|
|-0----------------------|-0--------------0-------|
|-------0--------3--2----|-------0-----------3----|
|-3----------------------|-3----------------------|

  G  G  G    E   C    B  A   F  F  E    C   D  C
  Happy Birthday dear ?  ?,  Happy Birthday to you.
|-------3----0-------------|-1--1--0-----------0----|
|---------------------0----|------------1---2--1----|
|-0-0------------0-------2-|------------2---0--0----|
|-0------------------------|-3-----------------2----|
|----------------3----2--0-|-------------------3----|
|-3------------------------|------------------------|
NB - Believe it or not, this song is copyrighted from a hundred years ago. If you use this music in public in the US, you're meant to pay Time-Warner/AOL for each performance. They make $2 million a year from it. Naturally the two women who wrote the song are long dead. I imagine they never made a penny.