One thing I have always told my students: “Include something red”. OK, that is a little exaggerated. But there is a grain of truth!
Look at today’s image, of the Hoover Dam:
What makes this a good image? Well.. I would say: the wide angle, the colours, the tilt, the rule of thirds, the curves, and, as the cherry on top, the red car. A little contrast like that is great. Juxtapositions. Contrast. Storytelling. And red, in a green and brown and blue nature scene.