Do your best to fill any gaps in your knowledge. You might not be aware that there are any gaps - after all, if you just finished a graphic design degree, surely you know everything you need to know to get started? Right? Wrong. You never stop learning. Years after starting my graphic design career, rarely a day goes by when I don't learn or teach myself something new. Diversification is key in graphic design.
Hopefully this site will have given you a good knowledge of what you need to know from a technical point of view before landing your first job. The information here is not advanced for today's graphic designer - it's essential basic training. If you know and understand everything here you should be able go into an interview confident, knowing that you are armed with everything you are likely to need to know to do a print-oriented graphic design job.
* Do take examples of relevant work along to the graphic design interview. If you have something that's been produced in the commercial arena, great. An interviewer is going to be interested in what sells, not what looks good on a wall. If you haven't got any work that you've produced as professional graphic designer, try to put together a portfolio of projects which you've given yourself to do. For example, design some new stationery for a fake company along with a brochure, advert and anything else you can think of. This shows that you're interested enough in getting a job that you're willing to put effort into proving why you should get it.