I agree it's not that hard to do. I was only shown once how to do it, when I, "won", a load of stripped out 2H2.5 from work and later rewired my garage and outbuildings with it.
Have a practice at ringing and stripping the excess length to check that the cable is still in a fit condition to be re-used.
No purchase needed, and if the copper has become too hard to work then an alternative solution has to be found!
Don't however leave the open end unprotected for long as it absorbs moisture from the atmosphere, then it is knackered.