I left my old personal blog alone for a year and then all of a sudden it had a good page rank. That's the easiest strategy so far. I suppose age matters in page rank. Then again, you can only afford to do this if you have the time to wait.

My other job blog got a page rank after only two months. I didn't use backlink strategies but I think the rank came from the good traffic that came in daily. This particular blog is in demand in my local region because of its content