As someone who has worked as a manager for over 13 years in a retail environment, I though I'd give a little advise for those looking to get hired, from the hirer's perspective:
1)Dress "business casual" for both an interview and when you pick up the application and drop it off (shirt and tie is overkill for most retail places, but you want to look like you care about getting the job)
2)Don't be rude to an employee, make a mess, or complain about something; then ask for an application (yes I've had people do this). If you fill it out there, be sure to do it somewhere out of the way, and bring your own pen.
3)The first thing I look at on an application are the hours available to work. The more the better. If you can't work the times I'm needing someone for, you won't be considered past that. Don't lie, if you have to work around a class you're taking, put it down. But if you'd just rather not work Friday nights, list yourself available. If you make it to an interview tell them there that you'd prefer them off but are willing to take turns, most managers will work with you.
4) The second thing I check is job history. Especially reasons for leaving. "Personal" or "Will explain at interview" are red flags. People who are only at jobs a few months at a time can also be a concern (I don't want to go through the bother of hiring and training you if you're going to leave in two months and make me start over). Even if you've hated your previous jobs, be as positive as you can about them. Oh, and don't lie or leave off jobs - they'll all show up on the background check most employers do these days.
5) References aren't as important as you think. Most big businesses will only confirm that you worked for them because they're afraid of getting sued if they say anything negative. Most applicants are smart enough to only put down personal references who will say good things about them, so these days references are almost useless. The exception is if you know someone who already works at that company who will put in a good word for you... as long as they are a good employee this can really help.
6) Please fill out the application completely. Don't leave questions blank and sign everywhere that calls for a signature. Put down phone numbers for previous employers - if I have to look them up, I probably won't bother with you.
7)Bosses are humans too, and for us, hiring is work. If you make our job easier, we'll notice. Dropping by and asking if the position is still open may just land you an interview, if only because it saves us making a phone call to someone else to set one up later.
8)On the other hand, when people call to "check on the status of their application" I just find that annoying. If your app makes the cut, I'll call you for an interview.
9)At an interview, smile and be as outgoing as you can. We're looking for someone who can be flexible with their schedule (meaning this job will be the priority for them), has a good work ethic, and who will be friendly and patient with customers - that's what you want to convey. Ask questions about what the expectations are. Be ready to tell stories about times you've given excellent customer service, resolved a customer complaint, or just made someone's day.
10)Finally, if, as they describe your responsibilities or required hours or whatever, and you realize that it isn't something you want to do, don't be afraid to say so and turn the job down. You'll both be better off in the long run.