Keeping permalinks from past posts, but switching to WP permalinks going forward

Forgive me if this has been addressed. I’m brand new to WP. My current blog is hosted on blogger using a custom domain. That was the extent of my web development experience, and that took me forever to figure out. Today I decided to try and get a WP blog up and running. I’ve not updated my DNS yet, as I want the site to appear “done” before I direct my current traffic to the new site.

My question is this…I’d like to keep the permalinks from my old posts that have already been indexed by google, as I get quite a few hits daily on several of them and they rank highly in search results. Going forward though, I’d like to go to a different permalink structure, say http://www.example.com/post-title or something similar. Is this possible? How do I accomplish this?