« Reply #10 on: Thursday 23 June 22 12:45 BST (UK) »
could it be a bit like 'shake a leg'?
which could be 'hurry up', 'get a move on' or possibly 'dance'.
The nature of the gathering or who the other attendees were might give more of a clue.
One of my grandmothers (from Yorkshire) would often say "get a shake on" when she meant to hurry up / get a move on
Berks / Oxon: Eltham, Annetts, Wiltshire (surname not county), Hawkins, Pembroke, Partridge
Dorset / Hants: Derham, Stride, Purkiss, Sibley
Yorkshire: Pottage, Carr, Blackburn, Depledge
Sussex: Goodyer, Christopher, Trevatt
Lanark: Scott (soldier went to Jersey CI)
Jersey: Fowler, Huelin, Scott