Armoured Cable

I have run an armoured cable outside in the garden and need a supply nearest supply is the boards so will fit a weather proof box with a40amp fused switch, it also needs a earth should I use an earth rod, then do I connect into a connecting box and then run the tails into the boards box for them to connect, the cable will be glanded also what do I do with the earth, does that also go into the boards box? I have permission from the board to run the tails into their box,am I right so far,
Regards
sailaway

for a diy install its generally best to use the houses earth. Whilst there can be advantages to a seperate rod and the recs sometimes don't reccomend using a PME earth for outbuildings a badly installed rod earth is imo a much bigger danger.

if you do go ahead with an installation like this make sure that there is a notice by the main CU to indicate that it does not isolate the outbuilding supply.