Character design is the part of my practice I've studied most deliberately, and the insight that changed everything was thinking about silhouette first.

A strong character reads clearly as a thumbnail. You should be able to cover the face and recognize the character from shape alone. This is why good character designers exaggerate proportions, accessories, and outlines — clarity of read at small size.

I test every character design the same way: shrink it to 100×100 pixels and ask whether the read is clear. If the distinguishing features disappear at that size they're probably the wrong distinguishing features. Add shapes to the silhouette, not detail inside it.

The second thing I learned: design for your most important angle first. For a game character that's typically a three-quarter front view. For a webtoon character it might be a side profile. Design should work perfectly at the primary angle and reasonably well at secondary angles.