Let's shake on it بیا با هم دست بدیم (به نشانۀ توافق)

shake on it  

MAINLY SPOKEN
used for saying that you want to shake hands with someone in order to show that you both agree to something:
Lance held his hand out and said, Let's shake on it.  

They shook on the deal.
Let's shake on it.
Carter stood up. "Let's shake on it." He held out his hand.
Can the two leaders shake on a deal that will bring peace to the Middle East?
"That's a deal," I said, and we shook on it.
Are we gonna shake on it?