get down vs set about

get down and set about both are verbs.

Word	Noun	Adjective	Verb	Adverb
get down	No	No	Yes	No
set about	No	No	Yes	No

As verbs, get down and set about are synonyms defined as:

get down and set about: take the first step or steps in carrying out an action

Other synonyms of get down include begin, commence, get, set out, start, start out.

get down (verb)	set about (verb)
take the first step or steps in carrying out an action	take the first step or steps in carrying out an action
put down in writing; of texts, musical compositions, etc.	enter upon an activity or enterprise
pass through the esophagus as part of eating or drinking	begin to deal with
lower someone's spirits; make downhearted
move something or somebody to a lower position
alight from (a horse)
lower (one's body) as by kneeling