When light enters the eye, vision is automatically redirected toward it. The eyes naturally rest on white areas which give them a soft place to land. Side lighting or back lighting give the best look, but it’s tricky. I try to avoid a halo effect, sun flare or haze unless I’ve planned it. I like going for a clean, natural look or an editorial look. I can accomplish this best during golden hour, cloudy days, or in open shade. I prefer details so I try not to overexpose, but sometimes I will for skin tone by half a stop. My go-to manual/RAW settings are f/2.8, a 1/250 shutter speed, and typically keep the ISO at 200.