What to do if your editor does not reply and there is no one else to contact?
See if you can download the PDF from the journal submission website. The editorial management systems I'm familiar with will take the author-submitted source files and generate something, which can then be downloaded by everyone (including the author). In fact, some editorial management systems will generate a preview for the author to approve before the submission is formally registered. If you've not received a "submission received" email, there's a chance that it hasn't been submitted right. 

Otherwise, it has only been one day. One day really isn't a lot of time (especially since it's currently a weekend). Even if someone usually responds in one day, he could be ill or on leave. I would wait a bit longer - maybe 2-3 more days.

If the manuscript was submitted correctly and there's still no response from the editor-in-chief after 2-3 more days, I'd email the publisher. You mentioned you can't find an email for the journal's editorial assistant, but you might still be able to find a "contact us" link on the publisher's website, and they'll be able to redirect you to the right person.