step to

Verb

 * 1)  To challenge, confront or fight (with someone).
 * Walter was angry, so he stepped to Bill.
 * 1)  To meet a challenge or confront (someone).
 * I couldn't let that insult go unchallenged, so I stepped to him.
 * 1) To begin (a project or plan) quickly or urgently.
 * We got permission, so you had better step to it.