Below, find a flow chart to help you make your decision. For more information on your options, check out "Here's how to figure out whether you should do your own taxes."
Bear in mind that these questions represent guidelines, not set-in-stone rules. If you find that you have extremely simple taxes but want the peace of mind that comes with a professional's help, or have extremely complicated taxes but feel comfortable tackling them yourself, then it's up to you to file the way you think is best.
As long as it gets done by tax day, you're doing something right.