Signing: Make your non-dominant hand into a fist, then gently stroke it away from your body with your dominant hand. The sign is as if you were gently stroking a little creature. When you do the sign, the motion should be slow and your body language relaxed.
Usage: Gentle is a good admonition to warn your child that they need to care with something because it is fragile. This comes in useful as children get older and they don’t realize their strength can easily break things. A lot of people keep using the sign even when their child gets older as an easy way to remind a child that might be playing a little too roughly, without embarrassing the child.