Hold them close enough to baby's face for her to see the snail, fish, cricket, and parrot -- about 8 to 12 inches away. It'll be fun to watch her react -- and you'll be boosting her ability to focus on new objects.
Here are some ideas to maximize their use:
Newborn: Print and affix them everywhere: under the hood of baby's stroller, to a place in her line of vision where you feed her, or on the wall above her changing table.
How-to: For the stroller or car seat, print them out on adhesive-backed labels; then just cut, peel and stick. For the walls, use removable double-sided tape.
2 to 4 months: Print multiple copies and make a mobile to hang above baby's crib -- she'll be old enough to entertain herself with while you step away for a few minutes. (If you have an older kid, make one to hang from the ceiling light fixture in her room. Bigger kids will get a kick out of these, too.)
How-to: You or your older kids can blow the mobile to make it move above baby's crib. By this age, most tots will be able to follow the critters as they move. Just make sure baby can't reach it -- either raise or remove the mobile as baby gets older and more dexterous.
6 months: You or your older children can color the images with bright markers and attach them to baby's ExerSaucer or play yard. By this age, baby's focus will be sharper and she can see in color.
How-to: Use these printables as personalized labels for your kids' toy bins. Print them out on adhesive-backed labels and use the dotted line as a guide for cutting.