There is a simple way. You can connect resistor in series with capacitator. Of course resistor must have very small resistance - 0.1 Ohm for example. Even in case that current change ( ripple ) is about 0.1A you will see it with simple scope.
The method of moss is simple but keep in mind that this only works in series with the ground lead of the capacitor and even then there are possible measure errors when ground is not the same ground as oscilloscope ground.
And if capacitor is not connected to ground it does not work at all.
use differential input of scope if available.