There are many ways,... this is what I would do...wait until dark, take a good strong garbage bag and spray a good dose of wasp killer in, [small opening of bag], then holding it closed. Get into position, very quickly, 2 or 3 second move, over the nest and into the bag, tie up the bag and quickly put away somewhere in the garden and leave it over night.
Konrad

Before you take Konrad's advice, I would either invest in a bee suit, or otherwise wear heavy clothing, gloves, and boots. Be sure to tape shut the pants and shirt cuffs. A bee helmet would also be advisable.

Thanks for the advise. I'll be very careful.