How to create an entry level resume? what should be include in the resume due to my experience?

Recently, my work experience isn't strong or long enough.when I was 16, I had work in Kmart in May 2007 but only work about three months due to company downsizing/layoff. In April 2008, I went to vocational school because I want to start a new career and want to work in a professional. At that time i didnt know what i want to be in the career. I was taking a trade Office Administration; completed everything. I did my internship successful but I didn't get hire because my old boss is not hiring people at all. I was a office assistant to her.when i completed my vocational school. i been trying to find a job in the administrative field. Due to economic recession and entry level experience, it was twice as hard for me to get a job either administration or one of those job like McDonald, Burgerking, or etc. My mother give me an idea that I should consider to be in the medical field because in the medical field they was always hiring people. I went to medvance institute and my trade was medical assistant. at my internship, i earn perfect rating at internship but at the end there wasnt hiring at that time. P.S. I move from miami to san antonio for opportunity and i am suck when it come to creating my resume.And Any advice that should help me get me start on medical field.