Working with Java Moss in the bowl
Free floating java over grown in one of my minnow bowls
To propagate I'm going to start by removing part of the clomp either by pulling the strands apart or by using scissors
close up of a section of java moss that has been extracted from a bowl.
  placing java moss into a new bowl can be done several was. One way is to just place a small clump in and let it float freely
You can place java moss in the roots of another plant like those of this spider plant. I've grown quite a few spider plants and a fair amount of java moss using this method.
Another recommended method is tying the java moss to a piece of drift wood or this lava rock. While the moss could be placed under the stone to hold it in place the portion of the plant under the rock will eventually die.
Java moss that has been established in bowl for 4-6 weeks
Java moss at 10X magnification
Java moss at 60X magnification
Java moss at 200X magnification