Always seems to go hand in hand with Hugey Wugey and Teeny Weeny currently. The actions are the same, but exaggerated, so for Hugey Wugey you imagine a tarantula-sized spider with your whole hands and for Teeny Weeny you use the tips of thumb and pointer finger. Voices can be correspondingly low and high.
Incey Wincey spider climbed up the water spout.
Down came the rain and washed the spider out.
Out came the sunshine and dried up all the rain.
Incey Wincey spider climbed up the spout again.