The giraffe sign is like outlining the long neck of a giraffe. Make your dominant hand a 'U' shape, with the palm of your hand facing toward you. Start down a little below your neck and extend the hand up and outward, ending up above your head.
Use the giraffe sign with the books and flash cards. Playing animal signing games is something that children really seem to love.
Your baby will love to learn the sign for giraffe with the help of the flash card or when using a toy giraffe. Consider taking a mini deck of flash cards to the zoo to help your baby contextualize exotic animals.