How is transfer impedance of a cable different from its characterstic impedance
Transfer impedance:

Transfer impedance is used to determine shield effectiveness at lower frequencies (&lt; 1 GHz) against both ingress and egress of interfering signals.

This is an indication of how "easy" it is for external signals (outside the cable) to couple to the signal being transported by that cable. An ideal cable would block all signals from the outside.

Characteristic impedance:

The characteristic impedance or surge impedance (usually written Z0) of a uniform transmission line is the ratio of the amplitudes of voltage and current of a single wave propagating along the line; that is, a wave travelling in one direction in the absence of reflections in the other direction.

This description is more cryptic, characteristic impedance is a property of the design of the cable. This is not an impedance you can measure with a multimeter ! You need a network analyzer or cable analyzer to measure this directly.

When transporting a (high frequency) signal through a cable you do not want to distort that signal. For this you need a cable which can handle the frequency of the signal (not attenuate it too much). Such cables have a characteristic impedance which you must use to feed the signal into the cable but also to terminate the cable with at the other end.

This is similar to how a transmission line must be used. If the cable is 50 ohms it means that the impedance driving the cable must be 50 ohms and that the termination impedance at the output of the cable must also be 50 ohms. If you would use different values, the signal would reflect and distort itself.

You can also indirectly measure the characteristic impedance of an unknown cable by feeding a pulse into it while observing the voltage at the input of the cable. At the other end of the cable terminate the cable with different values like a short (zero ohm), open and 20, 40, 50 , 75 ohms etc. There will be a certain impedance where the pulse will not be reflected and that is the characteristic impedance of the cable.