Q: How do you use bobby pins properly?
A: Wavy side down against the scalp. That side grips the hair rather than sliding over it, and it is the single most common mistake. Slide the pin in at an angle towards the section you want to hold rather than straight down.
Q: How do you stop bobby pins slipping out?
A: Cross two pins in an X where you need real hold, and work on hair that is not freshly washed. Clean, slippery hair gives the pin nothing to grip, so a little dry shampoo or texturising spray makes a noticeable difference.
Q: Do bobby pins damage hair?
A: Not in normal use. Damage comes from dragging them out rather than sliding them, or from reusing pins whose protective end tips have worn off. Replace any that have lost their coating.