Variants of this expression are watch the pennies and in the USA pinch the pennies.
Related Idioms :
count your chickens
treat something that has not yet happened as a certainty – informal
This phrase refers to the proverb don't count your chickens before they're hatched.
count imaginary sheep jumping over a fence one by one in an attempt to send yourself to sleep.
1977 - Harvey Pitcher - When Miss Emmie was in Russia Did you know that if you count sheep, it is watching the sheep jump that sends you off?
count something on the fingers of one hand
used to emphasize the small number of a particular thing
1992 - Fly Rod and Reel - Two decades ago one could count on the fingers of one hand the saltwater anglers who had caught a sailfish or a marlin on a fly.
count to ten
count to ten under your breath in order to prevent yourself from reacting angrily to something.
out for the count
unconscious or soundly asleep
A North American variant of the phrase is down for the count. In boxing, the count is the ten-second period, counted out loud by the referee, during which a boxer who has been knocked to the ground may regain his feet : if he fails to do so he must concede victory to his opponent. A boxer who manages to rise with in the count often is said to beat the count.