Partial balance transfer between credit cards

[mushtafa]

I've just learned that it's possible to do a partial balance transfer on credit cards. What I'm stuck with though, is how do you do it?
Do you initiate it from the original card, or the new card? Is it easy to do?

 

[Maccy]

Balance transfer is initiated from the new card - put in the card details of the card you want to transfer the balance from and the amount.