It was a bit of a faff though, so I wondered if anyone has any tips
for making the job easier, or what tools to use, etc.

Well, I use garden cane and twine. I've heard of people using toy guns
firing some sort of projectile attached to some despooled thread. This can
be used to pull through the string and then the cable.

If the ground below is smooth, I've even heard of cheap radio controlled
cars, a mirror and a torch being used in a similar manner. I doubt either
method would handle sleeper walls well.

Christian.