What looks right (angel from x-men) is quite far from what would work.
This is technical and ignores magic obviously. Bone density is the main drawback with flying. (on the other hand this doesn't stop dragons from flying) Take a look at the albatross. It has a large body for a bird and the wing span is enormous. A swan's wingspan is gigantic compared to its body.
Most, if not all, large birds fly by gliding not by being able to flap fast.
A human wingspan would probably have to be in the region of three to four times its height, unless they had 'chicken bones' reducing their weight.
Look how large a parachute is. Even a para-sail and they only slow down descent.
Para-gliders are enormous and they have no propulsion whatsoever.
So, as big as a hang-glider:
For 'reality'. Otherwise:'Angel' from x-men for looking good.