Scenery is an immensely broad topic, but for beginners there are some key composition rules to remember, and beyond those one’s personal style and the specific situation are the most important factors.
First to consider is framing, and the ubiquitous “rule of thirds.” This rule states that if one divides the frame into 9 squares, three sections vertical and three sections horizontal, the subject should be placed in one of the side sections rather than directly in the center as many people do instinctively. This usually creates an arrangement that is more pleasing to the eye. One part of this technique is to not include too much sky in the scene, unless it is a part of the subject. Many people tend to place the horizon line right down the middle of the frame, which is usually not the most pleasing place for it.
This photo breaks the horizon line rule since both the clouds and the dock are key subjects, creating a reason for balance. Note the Rule of thirds being applied elsewhere to the dock and large cloud bank.