wear a pair of hiking socks...really thick ones coz they go half way up your calf and have a lot of elastic support and stuff...that way the mic would stay in the sock, be easy to retrieve, and wouldn't be noticeable at all!
...and if this works i'd like a copy of the gig please...hehehe 
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see i'm feeling everything - nothing gets by -
and if i could be who you wanted...all the time
guess im just to young...to keep good love from going wrong
im not god - no - im not god.i may love you,but I'm not god -