Basically you use one action: it either is the one you take when you finally act, or it's the one you lose at the end of the cycle if you fail to act.
We've been doing it that the CA is used when the player declares the delay (that's when the player tosses the poker chip into the middle), but then when the character acts, the player doesn't need to throw in another chip. If we get to the end of the round and the character still hasn't done anything, the CA is already 'spent'.
The main thing to focus on: you can't use delay to save up CAs for later in the round -- you have to use a CA every time through the initiative order.
Steve