How do you take advantage of it and get another shield sent to you for free?

cough* tell them you installed it wrong, and you are not satisfied

I've done it twice so far. Just call and tell them that you installed it wrong, or were not satisfied (like already posted) Or, say it got ruined while protecting your ipod. Then poke a hole in it (not making it look TOO obvious) or scratch the hell out of it (which is VERY hard. I took a stiff metal brush used for scrubbing rust off of metal and it STILL didn't scratch)

Best protective product i've ever owned. Period.