How do you play when I'm 64 on piano?

To play "When I'm Sixty-Four" on piano, start by familiarizing yourself with the melody and chords. The song is in the key of E major, using chords like E, A, and B7. Break it down into sections, focusing on the left hand for the accompaniment and the right hand for the melody. Practice each part slowly, gradually increasing speed as you become more comfortable with the transitions.