Ebrake...cable line...

i was wondering …how do you tighten the ebrake cable line in the back were the Disc brakes are…i know howto tighten it from the ebrake but how bout from the disc brake pads…thanks because when i pull ebrake really hard…my right side only grabs…and my left side isnt tight enought cause the left sides not tightend…well it will be cool if anyone can help… thanks…