There was a chubby snowman 

(hold arms around body like you are chubby)

Who had a carrot nose.

 (with one hand make a pinching motion and pull it out from your nose to insinuate a carrot shape)

Along came a bunny 

(hold up two fingers and make a hopping motion)

And what do you suppose?

 (shrug shoulders)

That hungry little bunny

 (rub tummy)

Was looking for his lunch 

(hold one hand over eyes and look around)

He ate that snowman's nose....
Nibble, nibble CRUNCH!  

(use hand to make a chomping mouth actions at your nose)