Just to throw another basic thing at you, pay attention to the focal length you set on your (I'm assuming zoom) lens. Wider angle (lower number) not only increases field of view, but also depth of field, and stretches space. Going toward telephoto (higher number), yields not only a narrower field of view, but less depth of field (aka shallow focus), and compression of space. Like aperture on still subjects, choosing your focal length is one of the basic decisions you make when taking a picture. It's anything but just zooming to get the frame size you want.
A simple, telling exercise. Shoot a medium closeup (from chest up) of someone at the wide end of your lens, then step back and shoot the same size closeup at the long end of your lens (highest number) Do this outside in a place where there is space behind the person before you get to other houses, trees or whatever. Note how the subject and background look dramatically different, feel different, in each shot.