How to judge a woman's age by her appearance?

Nothing more than looking at the face: the depth of facial wrinkles, especially the corners of the eyes and forehead;

Look at the neck: the number of stripes in the neck wrinkles;

Look at your hands: the wrinkles, lines and slack skin on the back of your hand can be covered by makeup, but the back of your hand can't.

Basically, that's all you can show.