What does the cryptic crossword clue "We rest nervously after donning a garment (7)" mean?

The definition is "garment". The wordplay uses an anagram. anagram of WE + REST + A = SWEATER; definition: "garment" The answer is SWEATER.

We rest nervously after donning a garment (7)

Daily Mail Cryptic #17314 | 27 Across | 2024-03-14 flower