How to hook up my 2nd SUBWOOFER?

i got a jbl cs300.1(300rms) amp. right now its hooked up to a 10" sub 250rms. i just got a dual ported box and bought the same exact sub. question is i didnt install the previous sub. what do i need to do exact in easy steps and what do i need...im guessing speaker wire to send to the amp and the other end to the sub.