What does shift not yourself in the sight of others nor gnaw your nails means?

The phrase "shift not yourself in the sight of others nor gnaw your nails" suggests maintaining composure and confidence in social situations. It encourages individuals to avoid appearing anxious or fidgety, as these behaviors can signal insecurity. Instead, one should strive to present themselves with poise and self-assurance, as this can positively influence how others perceive them. Ultimately, it emphasizes the importance of self-control and self-presentation in social interactions.