The potato wedges in this recipe are crispy on the outside and soft and fluffy on the inside. This makes for a delicious potato wedge. Here is how to make your potatoes crisp on the outside. Soak the potatoes in cold water help to draw out enough starch to make the outside of the wedges more crisp. Lightly spray the wedges with oil before placing them into the air fryer. Leave enough space between the potato wedges for the warm air to circulate around.