when i changed from CC to a DSB i did the following.
First off, i had alot of rock which i wanted to get out of the way. so i went to Home Depot and got the largest (and cheepest) rubbermade boxes they had. i ended up getting two of those and using all the buckets i had (i do alot of fishing so i had buckets galore) I just made sure everything was washed out with fresh water and scrubed. no soap or any chemicals was used. just my elbow grease.
I then funneled most of the water into the buckets/containers. when i got the the bottom, i was able to scoop up all the CC. I then realized how much crap was in the CC. i then funneled all the rest of the water and crap out of the tank and into the drain. (lost about 5-10 gallons).
I then added the sand and a little bit of water. i stirred everything around really good until i couldnt see the difference between the water and the sand. i then funneled out as much water as i could. I then added the live sand on top (with the water that came with the bag (i hear that water is good to use)
I then used a piece of plexi glass and layed it on the sand. when i used my return pump to get the water from the containers back into the tank, i made sure the water hit the plexi glass. My coudiness was gone withing 6 hours, and it was perfectly clear the next day.