You probably need to understand the logic of hiring. One of my biggest gripes with graduates is when I don't get a sense of what they want to do. They just 'want a job with computers'. Computer Science is a good degree but there's a lot of areas that includes - IT specialist, programmer, developer, system admins are vastly different roles with different approaches and only a sample of what you can do.
It's a bit more involved than finding a job where the job spec says that CS degree is a must - you need to have a CV which expresses what area you are interested in. I worked in a call centre for a few months after graduating and left for a software engineering role after getting the first interview I got. Having experience might have helped but some of the CS grads I met there were still there 12 months after - having that job didn't make finding an IT or programming job any easier. My impression was they didn't understand the landscape of IT/CS roles, which made it hard to sell themselves.
Also one thing I did was got advice from one of the senior supervisors who also doubled up as IT support - he was actually being paid on the side to vet a Java book for a lecturer at a local uni aswell. He really got across to me the value of marketing myself properly - for instance when he was hired as supervisor he really sold to his boss why his degree mattered i.e. he could set up the server system that we used to log and track our calls and success rates, way quicker than a non-CS person. And he did - what would have taken someone 'learning on the job' 2-3 years took him a month + he understood important aspects of the system some self taught IT specialists sometimes don't get. He got paid better than other supervisors for it.
Selling the areas you are best at and finding roles to match, within itself is a huge plus. As would taking up side projects and using a personal website to promote yourself - at least with web development roles many hirers simply will not even speak to you unless you have a personal website of web development work and a huge online presence (LinkedIn, Twitter etc) as this promotion is what you will be doing as part of the job for their company.
Whatever works for you may involve temping/volunteer work, but the main thing is learning to sell yourself, then you can worry about your entry point. Sometimes with degrees like CS where you don't typically do a postgrad your optimal GPA or grade is minimum required + a tiny amount, where any additional work that would have been put into getting a first is put into summer jobs etc instead. But you can't change the past, just try your best. The thing is, getting a first only really matters when it's for a specialist MSc like quant finance where you might actually use what you learnt in the job. Getting a CS graduate degree just means you can "work with computers".