Composition organizes attention. Begin with the subject you want the viewer to notice, then examine the background, edges and relationships that either support or distract from it.
Use a three-frame exercise
Make a straightforward frame, move closer for a tighter interpretation, and then shift sideways to change the background. Compare the results before changing camera settings. The exercise shows how position can solve a problem that cropping alone cannot.
Lines, symmetry and off-centre placement are tools rather than compulsory rules. Judge each choice by its effect on the picture: where the eye enters, where it pauses and whether the important relationship remains clear.