Partly how one makes one's mark (10)
I believe the answer is:
apostrophe
'mark' is the definition.
(punctuation mark)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for apostrophe that I've seen before include "It may be superfluous on tradesman's sign" , "address?" , "Passage addressed to character" , "Letter omission indicator" , "greengrocer abuses it!)" .)