There were two scheduled sessions. The first began at 6pm and finished at 11.30pm, and took place in the control room of Abbey Road's Studio Three. Mono mixes of Taxman and And Your Bird Can Sing, one apiece, were made, along with nine of Tomorrow Never Knows.
The second session was in Studio Three itself, and took place from 11.30pm-3am. A number of rehearsals of I'm Only Sleeping were taped first, with drums and vibraphone on track one of the four-track tape, and acoustic guitar on the second, all of which were performed simultaneously.
After the rehearsals, 11 takes of the song were recorded, with the final one becoming the basis for the album track. They were performed in E minor, but the tape machine was running fast so it sounded slower and a semitone lower on playback. At this stage it featured John Lennon on a Gibson Jumbo acoustic guitar, Paul McCartney on Rickenbacker bass, and Ringo Starr on drums.
The Beatles attempted a remake two days later, recording five takes, but these were abandoned and the group used take 11 from this day instead. Those five takes from 29 April, however, were recorded over the first nine minutes of the rehearsal from this day. One of the surviving rehearsal performances was eventually mixed in mono and included on 1996's Anthology 2.