Arrange thus, right on time (4)
I believe the answer is:
sort
'arrange' is the definition.
(I know that arrange can be written as sort)
'thus right on time' is the wordplay.
'thus' becomes 'so' (synonyms).
'right' becomes 'r' (common abbreviation).
'on' says to put letters next to each other.
'time' becomes 't' (abbreviation).
'so'+'r'+'t'='SORT'
(Other definitions for sort that I've seen before include "Shuffle into desired sequence" , "fashion" , "Put in order" , "Arrange systematically" , "Type - arrange in groups" .)