easy, just clean the roots in room temperature water, do it in the dark preferably, and let the soil just fall off the roots in the water. get as much as you can its ok if theres a little left, after you put it into the clay pellets or lavarock just flush it a bit to get the soil bits out of the medium. May take a few days for growth to start but the roots will grow into the new medium just fine as long as you dont break them too much..