Look after infant, changing bib, say, on time
I believe the answer is:
babysit
'look after' is the definition.
(thesaurus)
'changing bib say on time' is the wordplay.
'changing' is an anagram indicator.
'on' is a charade indicator (letters next to each other).
'time' becomes 't' (abbreviation).
'bib'+'say'='bibsay'
'bibsay' is an anagram of 'babysi'.
'babysi'+'t'='BABYSIT'
'infant' acts as a link.
This may not be right. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for babysit that I've seen before include "Look after children temporarily" , "Mind" , "Tend to kid" , "Supervise in loco parentis" , "Take charge to allow parents to go out" .)