What is the origin of the idiom "keep one's eyes peeled" and when to use it?

The idiom "keep one's eyes peeled" likely originated from the practice of peeling or opening one's eyelids to keep the eyes wide open, which enhances one's field of vision and attentiveness. This expression emphasizes the idea of being watchful and alert of one's surroundings. It is used to encourage someone to remain watchful, alert, and vigilant, with a sharp and attentive gaze.