Hi Matem
there is not really a way to rig baits to avoid salmon and target kingies, the humble aussie salmon is par for the course in the cold waters at this time of year, generally once you find the kings, they are there in quantity... if you are afraid of loosing baits to salmon, try sending your fresh squid out in strips or as a head to give you more shots at bagging a king.
Cheers
Sam