What does the cryptic crossword clue "On bed, so set for whipping, bend over backwards (2,4,4)" mean?

The wordplay uses an anagram. anagram of ON + BED, + SO + SET = DOONESBEST The answer is DOONESBEST.

On bed, so set for whipping, bend over backwards (2,4,4)

Guardian Cryptic #29152 | 22 Across | 2023-08-18 flower