Short answers, pulled from the story.
Paul McCartney wrote the song Helter Skelter to create a sound as loud and dirty as possible after reading an interview with Pete Townshend. He intended the track to have the most raucous vocal and the loudest drums while serving as a direct response to critics who accused him of writing only sentimental ballads.
The Beatles recorded multiple takes during sessions in July and September 1968, with eighteen takes lasting approximately five minutes each recorded on the 9th of September session. The final version featured on the original LP emerged from these sessions where Ringo Starr later remembered the track as something done in total madness and hysterics.
Charles Manson told his followers that several White Album songs including Helter Skelter were part of a coded prophecy predicting inter-racial war between racist and non-racist whites. He employed Helter Skelter as the term for this sequence of events which he believed would allow him and his Family to emerge from an underground city to rule after black militants killed off surviving whites.
Siouxsie and the Banshees included a cover at live shows from mid 1977 before releasing a version produced by Steve Lillywhite on their debut album The Scream. Shock rock artists Rob Zombie and Marilyn Manson collaborated on a cover released in 2018 to promote their Twins of Evil tour that peaked at number nine on Billboard Hard Rock Digital Songs.
On the 13th of July 2019, the final date of his Freshen Up tour, McCartney performed Helter Skelter at Dodger Stadium in Los Angeles with Ringo Starr playing drums. This performance marked one of many times since 2004 that Paul McCartney has frequently performed Helter Skelter in concert across multiple tours including his 04 Summer Tour and The US Tour in 2005.