Insert a variable resistor with a range from 0.1 to 50 ohms in the output signal wire path of the driver where the ringing occurs.
Insert a variable resistor with a range from 0.1 to 50 ohms into the input signal wire path of the circuit whose output is ringing.
Connect a variable capacitor with a range between 1 and 100 picofarads and a variable resistor with a range between 100,000 and 1,000,000 ohms. Connect in a series where the unconnected capacitor lead is connected to the ringing circuit node and the unconnected end of the resistor is connected to the power supply voltage.
Adjust the variable resistor values in the circuit so that they are in the middle of the total resistance range. Do the same for the variable capacitor.
Connect your oscilloscope lead to the ringing node and apply the power. Adjust the variable resistors and capacitors such that the ringing is minimized as displayed on the oscilloscope screen,
Monitor the supply current of the circuit and the rise and fall time of the clock signal. Readjust the variables resistors and capacitor so that ringing is minimized; supply current is minimized; and the rise and fall time of the clock signal is minimized or all of these circuit specifications are within your required circuit specifications.
Insert a clock buffer or driver in signal path of the ringing clock line such that the driver is an equal distance between the circuit the clock signal drives and the clock driver circuit. Readjust the values of the variable resistors and capacitor so that ringing, supply current, propagation delay times and rise and fall times are minimized. Continue to insert clock buffers into the clock line in order to optimize circuit performance further.