In the DH panel:
* create a subdomain with nothing else on it, especially not Passenger, Wordpress, mod_rewrite commands or anything else that could interfere with WebDAV. Let's call this weave.yourdomain.com
* in Goodies>Htaccess/WebDAV, create a WebDAV directory:
Directory name http://weave.yourdomain.com/user (name has to be "user", literally)
Password protect YES
Enable WebDAV YES
User Accounts user123 pass123 (choose a username and password for Weave)
* install latest version of Weave (currently 0.2.7), it's under heavy development
* restart Firefox
* cancel the Weave registration prompt - this is just for the Mozilla server, registrations for the Mozilla server are closed anyway
* edit Weave preferences in about:config :
extensions.weave.username = user123
extensions.weave.serverURL = http://weave.yourdomain.com/
You need to edit them in about:config, not in the Weave menu. If you do it via the Weave menu it will keep prompting for registration.
* restart Firefox again
* now you should see the Weave icon in the statusbar. Click on it (or Extras>Weave in the menu) to set Weave preferences, log into your new Weave server and sync. Enter your Weave password and master password when prompted.
Alternatively, you could give the WebDAV directory some other name and tell Weave to connect to that directory. In that case Weave will create a "user" subdirectory.
More here: http://marios.tziortzis.com/page/blog/article/setting-up-mozilla-weave-on-your-server/
I would not recommend syncing your passwords over Weave for the time being, because Weave caches them in plaintext on your hard disk: https://bugzilla.mozilla.org/show_bug.cgi?id=438356