They often contain an acid, such as buttermilk, to react with the baking soda to help form more carbon dioxide. Since baking powder and soda start releasing the gas the instant they get wet, they should be mixed with the other dry ingredients and the batter should be used as soon as it is mixed. Have the oven preheated and the pans greased before you mix the batter. You can test quick breads for doneness by inserting a wooden tooth pick near the center of the loaf. It should come out clean.
Quick breads are very easy to make.
The only thing you must guard against is excessive mixing. The recipe will frequently say, stir only until dry ingredients are moistened. It means exactly that. The dough will look lumpy to you, but that is how it should be. This is particularly true with muffins.