Hands over, making exchange (4)
I believe the answer is:
swap
'exchange' is the definition.
(swap is a kind of exchange)
'hands over' is the wordplay.
'hands' becomes 'paws' ('paw' can be a synonym of 'hand').
'over' says the letters should be written in reverse.
'paws' reversed gives 'SWAP'.
'making' is the link.
(Other definitions for swap that I've seen before include "Fifty-fifty odds" , "Exchange; hands back" , "Exchange for paws" , "exchanged item" , "Exchange, barter" .)