Choose Your Focus Point, Then Lock It

Left alone, a camera often focuses on whatever is nearest or most contrasty, which is rarely a person's eyes. On a phone, tap the subject on screen; on an iPhone, touch and hold until AE/AF Lock appears, and focus and brightness stay put while you reframe. On most cameras, half-pressing the shutter button focuses and holding it there keeps that focus as you recompose. Exercise: put a mug close to you and a plant further back. Take one picture focused on each, then lock focus on the mug and turn slightly so it sits at the edge of the frame before shooting. Deciding what is sharp is the first real creative choice.