i do by follow step

1 i need modify the code
2 do the  git commit after modified complete
3 arc diff --update D3

this is ok?

See the documentation here: https://secure.phabricator.com/book/phabricator/article/arcanist_diff/

thanks chad ,I did it byarc diff --update id,also I have a problem about audit after post push the code,
how do i create audit after post push thanks

We document a lot of common questions, here's the Audit guide: https://secure.phabricator.com/book/phabricator/article/audit/

All the rest of the guides:
https://secure.phabricator.com/book/phabricator/

thank chad，I looked the document about the audit description,but i don't know to create Herald rules,

I typed “How do I create a Herald rule” into Google and our documentation was the first link. Did you read it?

O my god ,the herald rule entry is in config module,thanks chad

If you put Auditors: username1, username2 in your commit message, it will trigger an audit request to those users when you push it to a tracked branch.

I add the Auditors:pengrongxin in my commit message,but i don't receive audit request,this is why?