with the engine running - use a pair of insulated pliers & pull one lead at a time from the coils, until you find one that doesnt change the engine missfire - this will be the cylinder that is not firing.
swap the injector from that cylinder for another cylinder and see if the missfire follows the injector, or if it stays on the same cylinder.
If it follows the injector, the injector is bad, if it doesnt follow the injector, then you have a wiring issue, or something else entirely.
A missfire can be caused by a whole lot of things other than a bad injector.
Here are a few - Spark plug, plug wire, coil pack, low cylinder compression.
The injector control circuit fault can be triggered by a bad injector. if the ECU tries to fire that injector and gets no response it will fire the P0206 code.
