So basically 'say guhhh?' pretty much means what are you up to also known as what's up. It's a popular slang usually used on myspace/facebook and text messages.
Drake: say guhhh?
Brinkley: nothing much, watching tv.

You?
Drake: Getting ready to head over to garrets party.
You going?
Brinkley: nope, I don't have a ride.
Give me one? lol.
Drake: sure, I'll pick you up around 8:00.
Brinkley: see you then.(;
by Christine hunter July 6, 2010
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