Migrate Several Wordpress Websites (and 20 emails accounts) to DreamHost?

I just signed up with DreamHost. How can I easily move my 6 WordPress websites and about 20 email accounts from my current provider to DreamHost? Everything is currently active with my current provider. I have one site that I can move for testing purposes. I’ve read though the documentation and when I use the free migration tool I receive the following error message “Something went wrong. Please try again later.”
Thank you.

Take a look at DreamHost’s informative Knowledge Base:

The migration tool is now working, it wasn’t for my first site. Thanks!

thanks for the awesome information.