There are simple suggestions which can improve your photos, without having to spend a small fortune on camera equipment, or work yourself through pages of photo course materials.
What: The rule of thirds is easy to apply and it will really improve your photos.
Why: When you look at an image it somehow takes more effort to focus on the centre of the image. That is why it is a good idea to have the object, you want people to focus on, not in the centre of the image. Of course exceptions apply, but in general it works well.
How: When you take a photo imagine 2 vertical and 2 horizontal lines on top of the photo, in such way that you get 9 about equal squares or rectangles. Place the object of interest on one of the crossings of the lines. I posted a example below. The objects of interest are indicated by the blue circles. The rule of thirds can create a balanced interesting photo. Try it yourself. Also have a look at this video
It is as simple as that