How to get a Part Time Job

The method:

1. Figure out what kind of part-time jobs you are willing to accept. Try to break it down into 3 categories, such as: restaurant worker/bartender, 2nd shift office job, or laborer. The reason for this is that you will want to tailor your resume and approach differently for each type of job you consider. An office worker resume doesn't work well if you are going for a bartender job or driving a taxi.
2. From your 3 categories, craft 3 resumes that are tailored towards that type of work. Also, prepare 3 wardrobes in preparation for interviews. For an office job you might want a suit, for a bartender/restaurant job, maybe black pants and a black dress shirt or white shirt/khaki pants. If laboring, just dress neat but not over-dressed. (clean jeans, nice long-sleeve with no graphics)
3. Your approach for these 3 categories will be different as well. Use Craigslist, Monster, and other online resources to find leads, but don't underestimate the value of just showing up at a restaurant or business dressed well and with resume in hand. Just ask for the manager or owner, give them your resume and tell them straight-up what you are looking for. This open approach has worked well for me. For office jobs you'll want to go thru the proper channels by properly applying and sending in a resume before showing up.
4. After all that, the rest is just passing an interview. If being over-qualified has been a problem in the past, just tune yourself to focus on expressing your skills and how you can get the job done. Also put a big focus on your reliability. One of the problem with part-timers, especially students, is that they often have weird hours or show up late or other problems. You need to convince your employer that while your school work is a priority for you, it will in no way interfere with your ability to be on-time and do your work.

SOURCE