If you have no instructions for it then i would suggest carefully cutting back the outer and screen about 2” back from the end, pop the backnut, washer and compression seal onto the cable back from the trimmed end and push the “top hat” into the screen/sheath. Then offer up the assembly beside the connector and see how long the core needs to be to reach the solder fork on the pin. Then strip back the insulator a couple of millimetres so you have some exposed centre conductor. If you're happy with how it looks, assemble the connector and check that the centre conductor is the correct length and sits nicely in the solder fork; solder it in place and pop the cap on.
Done.