It's not easy getting directly into an IT security job after college without having related experience. The two most common routes to security that I see are experienced developers or experienced system administrators. The reason is because it helps to be an experienced developer to be able to spot code flaws, or to have experience in how systems are supposed to be configured in order to spot vulnerabilities due to mis-configurations.
Decide on what specifically you want to do in IT security. The network security field has a lot of specialties. Check out Lesley Carhart's blog posts on "Starting an Infosec Career". My reasoning is that there are different paths and certifications depending on what you want to do. Her blog posts talk about what each job is like and how the people quoted in the article got into those jobs.
Other things you can do that will show enthusiasm to prospective employers:
- Start a blog about security.
- Join a security related meetup group. I run one (757 White Hat Hackers) and I attend meetups at another local security group. Both groups have people in attendance that are trying to break into security. Our meetings are a great way to meet others, ask questions, and network.
- Use virtualization software like VMware Workstation Player or VirtualBox (both are free) and do security related labs in your spare time and blog about it. My VMware lab has a virtual firewall (pfsense) and various Windows and Linux servers that are vulnerable to various exploits and I use it to practice a lot in my spare time.
- In your virtual lab, download vulnerable virtual machines from vulnhub.com and work on hacking them. Blog about them and post your walkthrough's and include how to secure the same systems that you hacked (legally in your virtual lab of course). If you work on vulnhub.com virtual machines and don't know what to do with them, read other people's walkthroughs until you get the idea.
Go to security conferences, like the smaller regional BSides conferences and volunteer ahead of time. You'll meet a lot of people in infosec that way and they encourage volunteers and one of those people you meet may give you a break. If you're a volunteer you usually get in for free.
All of those things I've mentioned above are what employers look for in a candidate because it's not just about what you know or have done, it's also about showing enthusiasm and drive.
Best of luck and feel free to stay in touch and ask questions.