In the admin panel, check out the Packages tab (far right). I haven't used it, but it looks fairly straightforward to select what you want to safe, which will give you a .dfpkg download.
Install DF to your new host, upload your dfpkg file, and navigate to the admin panel again (this time on the new host). In the Apps tab, click "Import" on the left, and then use the "Browse" option to open your dfpkg file.