I am transferring all the components from one bike to make another, I have never done this before so could someone provide a step by step guide? Some parts are easy for me to imagine but I guess it is the cabling that I am most apprehensive about.
Cabling would be amongst the least of my worry - even if they can't be reused they don't have to be expensive and are not difficult to replace.
As the first step I would check beforehand that most if not all the components can be transferred across before embarking on the exercise. Are the frames for the same kind of bike, do they have the same rear dropout width, are the seatpost diameters the same, similarly for front mech clamp type/diameter, are the headset requirements the same, is head tube of donor not shorter yet not too much longer, is bb shell of the same size and type etc.
If the frames are not for the same bike "type" like road/tourer/hybrid/mtb e.g. a lot more incompatibility can pop up, including brake reach/type, or chainset suitability to name a few.