If you dont have any visible projects, make some. I recently hired an intern (well a couple months ago now) and he had built his own simple jQuery extension. It didnt do much, There were plenty of other libs out there that did the same thing, but he had his own library. I was like.. "WOW" this is the guy. He turned out to be an okay developer, and we were all pleased with his performance, and really probably the next candidate could've have done just as good.. but shoot, this guy had something visible and it demonstrated his abilities (even if it took him waaay too long to make, may not have been as fancy as it could've been, at least he took a stab at it). That Library gave us insight into his code before we even spoke to him.
Now for the Job part. Again, same answer just enhanced. You're going to want to have some good examples that they can check. You may want to build up your profile here on stack overflow, and reference it on your resume, just make sure to answer what you feel comfortable with, don't go answering complex problems and being wrong.
Some Jobs are looking for a "good fit" where personality makes a big difference, others want true skills. I wrote a quick on-line test and made every candidate take it before I would consider them. It weeded out a lot of candidates (it was pretty lofty, some of my fellow dev's couldnt pass it.. lol.. but it was intentionally hard). I also didn't expect many people to get them all correct. To me, the most important question was "why do you want to work here". We ended up finding some good well rounded candidates.
I've been on many interviews where i had to take a test also, and generally they're very hard. Again, just getting through it will gain you some kudos.
Now, once you have the job, you're pretty much going to have to really blow it to lose the job. Blow it like do a DELETE without the WHERE a good few times over.. Once they've gone through their process and selected you, the successful candidate, they're not going to want to do it again. That being said you can't get lazy. You must be willing to take on everything and anything and be willing to get answers yourself, maybe from Google, Stack, etc.. and get it done right.. People dont mind answering questions, but no one likes doing the grunty work of stopping what their doing to answer a question easily answerable from the interwebs..
So your checklist:
-Get some work visible
-Get your own domain (I've heard hiring managers notice custom domains and be impressed)
-Make some libraries (even if no one uses it or cares,
it gives people a sense of your style and ability,
-Wear a big smile, engage in conversaion
-Dont over dress on the interview. (we're programmers,
not customer facing, so dress nice (iron your button up),
but dont dress like you're going to a wedding.
Once you have the job, get ready to hit the ground running.
-Think about your work when you go home
-Dont try to introduce new technologies
-Get books and READ THEM.
-Learn the lingo, even if you dont know
how to implement it, you'll benefit from sitting in on the conversations.
-Dont bother other dev's with answers that are easily attainable..
go to them last so you can ask intelligently.
Good luck out there! You're in a growing field, There's lots of jobs out there so keep it up till you get one.
also, some advice some will definately disagree with:
Plan to Jump Jobs every 1-3 Years
many will say they don't like people who jump around.. but you're constantly facing new challenges, working with new teams, learning new techniques and methodologies. that will not do anything but make you more knowledgeable and valuable. You'll make lots of friends too.. dont worry, it's how we make more $$ these days..
and one last thing (since i'm on a soapbox already) Dont worry about jumping jobs and hurting anyone's feelings. You have to do what's best for you. If you find yourself gettig stagnant, start looking. You have to stay interested, otherwise you'll get bored staring at the computer day in and day out..
OH yeah, one last piece of info.. I'm an ART MAJOR (I was a programmer hobbyist)!!! so what you do in school will not at all limit you. Your Ambitions, Self-Motivation, Dedication and Interest are what will keep you sharp and moving up..
You're really only going to learn once you get out there.. so get out there!!