slighty off-topic... but willemvanoranje, which UC did you attend? I'm in my last semester of RA
I should probably apply for a PhD for fall 2011, since I'm going to get a 1-year MA. But seriously, I'm so exhausted I cannot handle another cycle yet... I started preparing over the summer, doing research and working on writing samples. Internships or summer school might be helpful, but I just work and travel during the summer so I used that as a strong point. "I love to travel and learn about other cultures" and gave some examples about how traveling has shaped my interest in and knowledge of history.
Good luck anyway, you can never start too early!