Need advice newbie here

I have a 06 2500 with a build auto, and a eja 4in straight pipe, maybe around 2" lift, and 35" tires. what is the best way i can get more power out of this thing. Im not to sure how to work the eja or how they settings work. everything else to my knowledge is stock. any advice is apprechaite.
(try to be decriptive if you can im new to cummins)

Thanks in advance