It's pretty hard to get an art related job in London, especially at the moment with thousands of graduating artists every year and similar amount probably moving to this cultural capital. I got the advice from many different people to do an internship first - this will 1) give you work experience 2) sounds good on your CV as you're keen to work for free 3) it gives you lots of new contacts if you do it in the right place. It helped me...and although it's not paid, I really enjoy it!!!
The next step is to use ALL your networking contacts, and go to the right places, events and organisations to expand this networking group. They say only 10% of the creative jobs are advertised, rest is through contacts. So, there PdC networking events come in handy ;)
Thirdly, check out all advertising places; sign up for the Arts Council mailing list, check the guardian website, also keep an eye on the job listings from your university (that got me my current work :) etc
...and of course a perfect portfolio, website and shiny CV...
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