You just need to work backwards. Is there spark at the distributor cap?
Take the king lead off and check if that is sparking to earth. If it does, then the coil is fine, and the fault lie at the cap/distributor (the ignition modules love to die - and the caps/rotor need to be clean internally)

If the kind leads doesnt spark - then its potential coil or col wiring. Again, easily checked with a basic multimeter