Frequencies

As we make our UAV fly we use multiple radio frequency bands for different uses : RC control of the craft, eventual telemetry band, eventual video downlink band (FPV or camera monitoring), GPS. An issue we have all already encountered are interferences between used radio frequencies. So how could we try to optimize, in a simple manner, the choice of our UAV's various radio frequencies (rc control, telem, FPV, ...) ?...