Make the bird sign by making a beak shape with your index finger and thumb and by bringing those two fingers together, while making a mini-fist with the rest of your fingers. Then tweet like a bird, by bringing your fingers together and apart.
This is one of my favorite signs!
When you see a bird, point it out and make the sign for bird. I often add a tweeting sound effect to the bird sign, to make it a little more fun.
You will want to supplement the flash cards with the animal’s sound. "Tweet … Tweet." Making the sound activates another sense and makes the experience more vivid for your baby, all factors that will help improve learning. It is also more fun!