It is one of those jobs which is character forming, I'm sure there are various shools of thought on how to do it.

Here's mine: Get the nut that goes inside the car and fix it to a ring spanner with a bit of tape, blue tack or whatever takes your fancy, obviously the hole through the middle must be unobstructed. Not too well fixed, remember the spanner must be removable

Then get the cable and push it through the bulkhead and the nut held in the spanner, an assistant is helpful at this stage. You then tighten the whole lot up on the engine side by turning the whole cable.

After that you put the cable in place round the engine and down to the bellhousing. Adjust the cable leaving a bit of play so the clutch release arm is clear of the thrust bearing, you will feel the arm connect with the thrust bearing as you push it towards the front of the car.

Incidentally the cable will work without the nut inside the car, but it is cheating, occasionally rattles, and somehow not quite the done thing

Regards