Life's Sonnet

If life's a sonnet. I don't know what iambic pantameter is, so help is good ;)

If life truly is a sonnet,
with the structure all worked out.
Rhyme, meter, timing, length; nothing left in doubt.
Then how to embellish upon it?
What's the point of feathered bonnet,
when God's will must come about?
When the rules you can't surmount?
Then life is fixed, and you just donne it.
Yet, there is room to decorate.
Plenty of space to make it "you."
Empty areas that soon will fill
by life's end with all you say and do.
Thus your sonnet's individual fate,
preordained life painted in free will.