If you can figure out how to do it, then you can do it yourself. If not, you'll need help from a legal professional.

It's usually a pretty simple, form-driven matter. Check with the court to see if there are any standard form petitions and orders for wage garnishment and, if not, check the county law library or a law school library for a guide to collections law in your state, as I would expect a practitioner's guide to contain sample forms and orders.