Learn piano chords – how to play 6th Chords on piano, and how to construct these chords http://www.zebrakeys.com/lessons/advanced/chords/?id=44/.
Access free virtual piano keyboard to practice playing this chord – http://www.zebrakeys.com/resources/musictools/virtualkeyboard/
More the formula of these chord lessons –
Major 9th Chords
Major 11th Chords
Major 13th Chords