The backing track was recorded in the day's first session, which lasting from 3.30-5.30pm.
The released version was take six. A longer version, known as take seven due to George Martin's erroneous announcement at the start, was most likely actually take five; the recording circulates on bootlegs, and ends with three minutes of jamming and screaming from Paul McCartney.
The Beatles used just two of the four available tracks during this first session. Rhythm guitar, bass guitar and drums were added to track one, and McCartney's lead vocals were recorded onto track two.
A second session then followed from 7-10pm, in which overdubs were added to take six. McCartney re-recorded his vocals onto track two, and George Harrison added a guitar solo onto three.
Track four was used for final overdubs. McCartney added piano, Ringo Starr shook a chocalho, and McCartney and Harrison doubled up their vocals and guitar solo respectively.