Step 1:
Buy some medium grade or large grade bark.
Step 2:
Soak the bark in water for a couple hours asap.
Purified water is preferred. If you can't get a hold of purified water, tap water is "okay".
Step 3:
Remove the moss asap.
When working with the roots, make sure they're wet. Wet roots are more pliable and less prone to damage than dry ones.
Step 4:
Repot into the bark asap.
Here're some pics of Phalaenopsis in the wild.
Phalaenopsis in situ - Flickr: Search
The evergreen Phalaenopsis are found in tropical Asian swamp forests growing as epiphytes. The trees have a little bit of moss to no moss on them.
Sometimes they're found growing on trees near rivers or streams.
Notice how they're positioned on the trees. Try to emulate this growth habit as best as you can in pot culture.
Temps: 55 F - 95 F
Light: shade to bright shade
Humidity: 60% or higher
Keep evenly moist. If you've successfully grown ferns, watering Phals are much like watering ferns.
Position the plant's crown (the crown is where the new leaf is emerging from) towards the light source.