If you have the means to, I'd definitely recommend you going into as many Research Assistant positions as possible. One of my friends is currently doing a Masters in Health Psychology, I think, and she's going straight into a PhD, and she's had a couple of Research Assistant positions (non-permanent positions, as the research only had so much funding) and she worked as an Assistant Psychologist for some Clinical group, but she wasn't paid. Financially, it's quite tough, but take any means necessary to get relevant experience. Plus, you make a lot of contacts