Here are some ideas for how the song could be used with actions.
'Down came the rain' could be both hands raised in the air and then falling down whilst moving the fingers. 'Out came the sun' could be the hands together making a circle. It doesn't really matter what you and your class choose. But you can be sure of one thing - your students will definitely know the actions of a spider!
Incy Wincy Spider
It's best to have just one action per sentence otherwise it gets too complicated. 'Incy Wincy Spider' could be a hand with wriggling fingers. 'Climbed up' could be the action of climbing up a ladder (the song has a water spout but this doesn't matter).'Down came the rain' could be both hands raised in the air and then falling down whilst moving the fingers. 'Out came the sun' could be the hands together making a circle. It doesn't really matter what you and your class choose. But you can be sure of one thing - your students will definitely know the actions of a spider!