Start by printing the valentines off using a color printer. Make sure you have your printer set to landscape mode before printing! There are four valentines per sheet, so make as many copies as you need.
Next cut out the animal faces, leaving a small tab at the bottom of each face.
Cut a cross in the approximate area of each animal's mouth. This is where you insert the whistle. To make sure the whistles stay in place, you may want to tape them to the card by adding a small piece of tape across the back of the card.
Address and sign the valentines, and they are ready to hand out!