Babies aren't people. They are
wretched little beings with
poop in their
pants that don't deserve the love and
affection that is often bestowed upon them. They are
oppressors. I will not tolerate
oppression.
1. Peek-a-boo! Every baby loves Peek-a-boo! You bring your hand-covered face close to theirs and with a clever "Peek-a-boo!", you reveal your mug, much to the delight of the young toddler.
If you must play this childish game for sissies, I suggest wearing a scary Halloween mask in the process. May I suggest a Hellraiser or shrunken head design? For added pleasure, use a generous amount of fake blood or ketchup that drips off the mask. The kids love that. Make sure your "Peek-a-boo!" exclamation is loud and nasal.
2. Babies love being thrown up as you say "weeeeee!" and caught on the way down.
I bet you thought I'd say, "let them fall". I'm not that cruel. Rather, throw them up in the air as high as you can and try to catch them with one hand. Added points for grabbing them by the face or hair. Babies love this. Also try using the baby in a game of catch should a baseball be unavailable.
3. All babies are full of joy when taking their first steps with those chubby little legs.
Make sure the baby takes his first steps on a medium-sized rug. That way, you can swiftly pull the rug from underneath the baby as s/he falls on his/her behind with a loud thump. If baby happens to be walking on a carpet or tiles, I would recommend practicing your dropkicks on baby's gut or forehead.
4. Babies are always looking at people. Don't forget to stare them down. Bonus points for making them cry.
Disclaimer: This may constitute assault or child abuse in your area. Check local laws beforehand and please do not take this guide seriously.