Answer:
A beacon from home to guide your way. It can be a lifesaver on a stormy day. What is it?
My voice is tender, my waist is slender and I'm often invited to play. Yet wherever I go, I must take my bow or else I have nothing to say.
What has a spot and is very bright, is sometimes, red, white, blue, yellow or green and is often blinding.
A circle of stones, never in rows. Stacked one on the other, mystery it sows. What is it?
No matter how little or how much you use me, you change me every month.
The more of me you take, the more I appear behind you. What am I?