What actually suits the hand
The back of the hand is the strongest real estate: a flat-ish surface with room for a contained motif — a moth, a dagger, a rose, a geometric panel, a small animal. Fingers suit short bands, single symbols and one or two characters per digit. Knuckles traditionally take four- or eight-letter words, one per joint. Side-of-hand and thumb webbing work for slim vertical elements. Palms and inner fingers are the least reliable areas; ink there often needs touching up and rarely holds crisp detail. As a rule, if a design still reads clearly when you shrink it to a thumbnail and blur it slightly, it will age on a hand. If it doesn't, it won't.
