count your chickens 
/ˈkaʊntˈjoɚˈtʃɪkn̩z/ idiom
/ˈkaʊntˈjoɚˈtʃɪkn̩z/ idiom◊If you count your chickens or (US) count your chickens before they hatch or (Brit) before they're hatched, you believe that something you want to happen will definitely happen before you know for certain that it really will.
▪ Don't count your chickens before they hatch—we don't know yet if she will accept our offer.
▪ Don't count your chickens before they hatch—we don't know yet if she will accept our offer.
