Make the hot sign by taking your fingers and thumb into a claw shape. Now starting with your claw hand over your mouth, move the hand away from your mouth and rotate it so that you end the sign with your palm facing outward. Flatten out your leading hand.
Hot is a useful intermediate sign to teach your baby when they start eating more independently. Babies will often not fully understand the laws of thermodynamics and put hot food in their mouth. When your baby puts something a little too hot in their mouth or hand, make the sign and wince a little to help them learn the sign.
A great way to teach the hot and cold signs is to use some warm and cool water and put your baby's hand or foot in each.