Thank you guys for the advice! Well, after reading this, and all the posts that I saw on other sites, here's what I ended up doing: I first soaked about half the bag and picked out everything that floated. Next, because I CLEARLY wasn't going to have enough to fill the pot this way, I also got some styrofoam and cut it up into small-ish pieces and mixed them in there. Then, I mixed in a bit of the actual straight-up mix (without the soak-treatment). I mixed all this together, took the orchid out of the moss and pot, trimmed its roots with a sterilized blade, repotted it, and watered it. Now, here's to hoping it's happy in its new home! :-)