How to backup/restore account

Apart from using a backup app like Titanium Backup for Android (which requires root), how can an average Joe do something like move from an old phone to a new phone?

Account backup and restore should become available several weeks from now.

Maybe there’s a way to back them up now by copying keys from debug logs, but there’s no way to restore right now, so unless they tell us that’d work we can’t know for sure.