Hi,
I would like to put one, maybe two sockets in my loft.
We used to have an electric shower in the bathroom but have since changed to a mixer shower. The cabling is still there, going into the pull-cord switch on the bathroom ceiling; it is on an independent 40 amp radial circuit.
Move the switch to beside the loft hatch and use it as an isolator.
This will be a convenient place to terminate your 2.5mm or 4mm cable.
But from what you are writing here I do't think your competant to do this work and for your safety and protection advise you to use a proffessional.