Begin by SLOWLY and carefully taking up whatever you can with a broom and dust pan. Lower the pan into the barrel all the way before dumping to avoid having dust kick up. Buy the Drywall filter for your shopvac - presuming you have one - they work GREAT! Again, when emptying the vac, take precautions to minimize dust kick up... you can also use a mist bottle to keep the dust down by spraying slightly the area - this keeps dust down, but makes a bit a of muddy mess as well. ... another thing you can do is buy a "sweeping compound" like these http://www.acehardware.com/search/index.jsp?kwCatId=&kw=sweeping%20compound&origkw=sweeping%20compound&sr=1 .. probably a bit pricey and I've never used it, but I've heard great things.