well, it's probably fresh out of tissue culture if you just got it, so you'll want to wait for next year till you put it in dormancy. the spring after dormancy is usually when you replant.
however, if your going to put it in a terrarium, you can either re-plant now, or just put the pot in there for a while, either way is fine.
When re-planting be very delicate, every fiber of a flytraps roots are precious as gold to the plant, keep the soil and root ball intact as possible.