Set to arrange plates in order (6)
I believe the answer is:
impose
'order' is the definition.
(thesaurus)
'set to arrange plates' is the wordplay.
'set' becomes 'pose' (synonyms).
'to' says to put letters next to each other (I've seen this in other clues).
'arrange plates' becomes 'im' (I can't justify this - if you can you should give a lot more credence to this answer).
'pose' put after 'im' is 'IMPOSE'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for impose that I've seen before include "Lay as burden, onus" , "Be a bother" , "As task, set" , "institute" , "Obtrude, force (on)" .)