O.K. ... what do you want to do?
Do you want to teach law in a college (to undergraduates)? There is a professional association to join, and you can get up to speed quickly. There are a steady stream of openings in community colleges.
Would you rather teach justice studies? If so, get some postdoctoral training and a background at a good university from the justice-studies part of the sociology department.
Do you want to teach in a law school? If so, you need to publish.
If you want to teach criminal-law paralegal classes, then you should contact the continuing-education program at your local junior college and start a class.
Think about what you really want to do.
This link may help get you started:
http://adrr.com/adr9/050a.htmBottom line: read the background material, do a little research, and consider your focus. Then decide if you need a postdoc (post J.D.) certification or if you can enter teaching from a different angle.