1. Wash your guavas. You should wash the entire guava, as the rinds are actually edible. Rinse the fruit with cold water in an effort to quell any bacterial growth. Pat your guavas dry with paper towels. 2. Place your guava on a cutting board.Using a knife, slice your guava in half.ou can wrap uneaten guava halves in plastic wrap and store them in the fridge for up to four days. If you donât think you will eat the guavas within four days, you should freeze your guava. Frozen guavas can stay in the freezer for up to eight months.