When looking under a bench, try tying your shoe or do push-ups!
If someone looks at you holding your GPSr, just put it up to your ear and pretend it's a phone, or you could pretend it's a camera! Pretend your taking a picture of the guy who's looking at you and he'll turn away!
Dress in camo and put camo grease paint on your face! No one will be able to spot you.
Ask dubord207. He has lots more ideas! Like telling people you are taking sizmonic readings of the earth....or something like that!

I hope my suggestions help!

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