Mode dial on A. Auto ISO. Eye detection on. RAW+JPEG. Shutter faster than 1/focal length. Focus on the eye. Watch the background. Find the light. Get closer. Shoot a burst. Everything else is detail.
Small print
This guide is general educational material and is not affiliated with or endorsed by Canon, Nikon, Sony, Fujifilm, Panasonic or OM Digital Solutions. Brand names are the property of their respective owners. Menu locations and feature names vary by model and firmware; always refer to your camera's own manual for your specific model.