What I did was I got one of those 20 gallon red party tubs at Target for like $3, put half my tank's water in it first, followed by all the live rock. Then I put in the tank's heater and powerhead and made sure they were running. Once all of that were in the tub, I netted the fish out one at a time and put them in the tub, then I picked out all the snails and hermit crabs by hand.
Once the CC was out and the live sand was in, I gave it about 4 hours for the dust to settle, then I put the live rock back in and finally all the fish and critters by net.
Finally, I returned the water from the tub back to the tank using a regular drinking cup (it took a few minutes but I wanted to make sure I wouldn't disturb the sand).
Not one single casualty was had that day!