Can someone please draw me a SIMPLE diagram showing how I wire up the second battery. From it for example, do I need an inverter so that I would have a set of power points.  From these points, to power the lights, blow heater, radio etc.,....Please make it simple.    Thank you..

There were no takers on my plea for help so I studied it myself. A)..Bought a Kemo M102N  2 accumulator charger (split charge relay)  fitted it under bonnet close to main battery. B) Took main charge wire from the alternator & fitted it via a 20amp fuse to input+ on the Kemo.C) Took earth of main battery & fitted to earth input on Kemo) D) Earth returned from Kemo to Main & Leisure batteries. E) Output + (1) from Kemo to main battery + with 20 amp fuse. F) Output+2 from Kemo taken to leisure battery with 20 amp fuse....All systems go & ain't it easy when you do it on your own.!!