I'll make you a deal.
→   이렇게 하면 어떨까?

[예문]
A:You can't dress like a nerd and say "cool" and "gnarly". You sound silly.
  공부벌레처럼 옷을 입고서 "쿨하다"거나 "짱이야"라고 말할수는 없어. 실없게 들려.

B:I'll make you a deal. I'll get some new clothes.
  You can help me pick out some cool clothes.
 이렇게하는게 어떻겠니. 내가 새옷을 살께.네가 쿨한옷을 골라주라.