Sarah knows her own wanking hand

Here's a brief description of the contestant's attempt. Someone's probably working writing up more detail!

When Alex took a photo of her hand, Sarah had decided to make her hand into an open fist, instead of lying it flat like everyone else. This made it much easier for her to find the photo of her own hand, so she made zero incorrect guesses, and earned joint first place.

(Written by Taskmaster Wiki contributors)