You can either start spraying the cage because they aren't currently humid enough or you can add a humid hide. For now, if there is still some skin, I like to let my gecko walk around in shallow water for a few minutes and then use a wet q-tip to encourage the skin to come off. Make sure the skin is wet and is ready to come off or you could hurt the gecko. Double check to make sure you get it all off, you don't want it hanging around too long