In article ,
Martin Angove writes:

Why has no-one mentioned the simple pen-knife yet?

Well, that's what I use -- normally a stanley knife.

When wiring, I usually try to avoid cutting the conductors
if they are to be connected back together in the terminal.
I remove a length of insulation and fold the conductor in
half or lay it through a slotted terminal.

When doing a whole ring circuit, I usually try to see if I
can install it as one single uncut length of cable from
the CU back to the CU. This way you never get any cumlative
contact resistances in the ring itself.

--
Andrew Gabriel