Make a good impression. If you're lucky enough to have an internship, don't ruin your chances of full time employment by slacking off. Instead, show your employer that you are full time material by maintain a professional demeanor at all times. Dress well, do your job efficiently and a show your independence from day one. Make your employer see you as more than a young intern fresh out of high school by working well with others, taking on extra responsibilities and generally showing that you fit into that workplace environment.
Set professional goals for yourself. You can also improve your chances of turning an internship into a full time job by setting professional goals for yourself and finding an internship that will allow you achieve these goals. Choose an internship that has the potential to lead to a career that matches your career goals. If you're in an internship that you truly enjoy, you'll be more likely to show the drive and competitive edge that will make you a candidate for a full time job with the company.
Get to know your boss. Even though you may be lowest on the ladder at your internship, you should still make the effort to get to know your supervisor. This is the guy or gal that's going to have the final say when it comes to hiring for a full time position, so you want to develop a relationship that will improve your chances of winning a permanent job. Don't be intimidated by age or experience. Be comfortable and professional around the higher-ups so that your face will be familiar on interview day. Ask for feedback about your job performance. Find out what skills your supervisor is looking for in an employee. Do whatever you can to exceed the expectations of your employer so that you will be considered for a full time job. (Plus, if this employer doesn't have any full time opportunities for you, he may still recommend you to his other supervisor friends. Anybody you can network with improves your chances of getting that full time position.)
Put your best effort into your internship. When you're working in an internship, consider yourself to be interviewing every day. Every project you work on, every phone call you take and everything you do at this company will be used to judge your performance. Make sure that you showcase a strong work ethic for the entire time of your internship. Maintain a positive, driven attitude and meet all deadlines. Ensure that you meet all expectations of you (including following company rules and guidelines). Avoid unprofessional behavior too - that's not going to get you into a permanent career.


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