As soon as your bird reaches the maximum level for its current evolution stage, you can evolve it if there is enough evolution materials of the same color as the bird. You can evolve the bird by tapping the village tab and selecting ‘Bird Team’ on the menu. 

Select the bird you’d like. As soon as you’re sure everything is set as it should be, tap the ‘Evolve’ button and see how strong the bird gets!

Four and five-star birds have two variants for the last evolution. You must select which one you want before you evolve the bird! Please remember that once an evolution is selected, it cannot be changed!

To evolve your four and five-star birds at level 60, you will also need Evolution essence of the same color as the bird. You can earn Evolution Essence from the dungeons.