One big mistake I made after I graduated was I never researched what I should be paid for my job even at entry level. I just took whatever seemed nice to me and now I am stuck doing something I should be getting paid a lot more to do.
A Graphic Artist should ge paid $30,000-$40,000. Entry level maybe $26,000. Hopefully after three years I will be able to get paid what I do.
Don't let people take advantage of you. Make sure you know what you deserve.