First of all, congratulations! You've slogged your way through and hopefully learned a thing or two in the process. However, I would like to remind you that although this is an important step, it is by no means the end. You still have a great deal of difficult work ahead of you. Often times the outlook can be daunting, even scary. This is normal. Many of you will find yourselves in a strange state of post-graduation limbo, not sure what is the "right" step to take next. This is also normal. Insecurity is normal, it comes with the whole "artist" package. The important thing, the defining factor, is work. Continuing to work in spite of everything else will get you through to your goals. Action is the best antidote to fear.
Here's a good little article on that topic.
So you've made it through school but your work still isn't quite where you want it to be? Ira Glass has a message for you.
Also, keep in touch with your friends from school. Don't be afraid to ask for help or advice. Don't be afraid to solicit criticism. Listen to people when they give you criticism, but use your own judgement in deciding how to utilize it. Contact the people you admire and ask questions. Momentum begets momentum, so try to keep that ball rolling.
This all probably sounds a bit corny, but from my experience I think it's true. Anyhow, good luck to you all and keep on keepin' on!