I found a reasonably priced battery operated alarm clock at Target. I chose this one cause thinking along the lines of the paranoid Rabbit's mind processes I figured the more accurate the numbers the better and this on even had numbers on the inner facing to count the exact seconds. Perfect!
I had some nifty thick chain at my house the length I needed and then I had some blue ribbon I just strung through the links to make it a more secure necklace.
It's important to note that I had a mini D-ring to fasten the two ends of chain together cause if the Rabbit is in a rush I didn't want the chain to come undone.
I threaded the chain+ribbon through the open top loop of the clock and tied the ribbon ends in a bow to make it look pretty.
I got more creative and used 20 gauge wire and little glass heart beads to make decorations to hand from the knobs of the bells.
That's all there is to it.