Couple other thoughts on lighting / composition:
"Soft" light is often the most flattering to skin. A pro photographer might use a big lightbox or umbrella. You can use the light from a north-facing window for free. Or hang a lightweight white sheet over a window that gets direct sun to soften it up.
"Hard" light (like a focused lamp) has its uses when you want to show off texture or profile.
If your phone has a portrait mode, make use of it - playing around with what's in focus and what's not can help steer the eye to where you want your viewers to look.
If you've got a regular camera, zooming in and using a wide aperture (like f/1.8) will have only a small part of the image in focus. One of my favorite recent examples of that is a picture from yesthatkat in #girls in late August (with a plant draped over her).
