Translations:Encfs/25/en

That is all there is to it - your jiberish unreadable data will now be on the web (in the cloud) in the Dropbox/encrypted folder.
It will only be readable to you after you have mounted ~/Dropbox_unencrypted on your local computer. You will also have the synced ~/Dropbox/encrypted folder on your computer , and that will be as unreadable as the content on the web.
As we have seen above; this content will only be visible when you mount it in ~/Dropbox_unencrypted.
Again; do not put any content in ~/Dropbox/encrypted: All the content there will be added after you have mounted the working directory - ~/Dropbox_unencrypted. To test it you can unmount it with

fusermount -u ~/Dropbox_unencrypted

and re-mount it with

encfs ~/Dropbox/encrypted ~/Dropbox_unencrypted

at wich time you will be prompted for the password.