As a grad/professional student, you will write (or already have written!) a LOT of papers. Rather than tossing that paper aside after you've received your grade, consider turning it into a manuscript submission. There are many benefits for publishing as a grad student:
Things to consider:
More resources:
A journal's Impact Factor indicates the average number of times articles from the publication have been cited over a two-year period. The higher the journal's impact factor, the more prominent the journal is in the canon of literature.
Author guidelines of most journals can be found on the journal website, which can be found via Google or by using Ulrich's.
Make sure to follow the guidelines closely and prepare your submission in accordance with these guidelines. Things like word count, format of the manuscript (text, illustrations, etc), and citation style are all very important.
Make sure to also check if the journal accepts submissions on a rolling basis, or if you need to inquire with the editor first.