set up PA2

Hi, im new with this audio PA2 set up.
i would like to set up my PA2 and keep it simple.
here is the problem we had someone helping us he robbed us by stealing the PA2, so we purchased another one but we do not know how to set it up. the sound it not clear. we just need a simple set up.
input from a 32 channel mixer- PA2 - transmitter (low watt) - output radio frequency.
it does not sound good at all cause we touch all type of buttons. now we need help.