Install the openssh-server package. It will prompt you to set up a root password (and make you enter it twice to be sure it was entered accurately). Once it's installed, it'll already be running. NOTE: PLEASE BE SURE TO ENTER IN A STRONG PASSWORD FOR THE ROOT ACCOUNT. Don't use dictionary words and be sure to sprinkle in a number or two. This is ROOT, after all.

You can immediately to go your Macintosh and ssh to your tablet's IP address as the 'root' user but I highly recommend against it.

The first thing I would do, if I were you, is go to the tablet's terminal once again and ssh back into itself as root to change the 'user' password so that you can use that account to place files onto your tablet. Here's how:

ssh root@localhost

When asked for the root password, enter in the root password you had entered when you installed OpenSSH earlier. At the prompt, enter:

passwd user

Give the 'user' account a good password as well and voila! Now you can go back over to your Mac and ftp to your tablet with the 'user' as the username and the password you had assigned to it.