Update: You can now host your ROM on ROM Manager's high speed server for free using ROM Manager Developer Portal! The following instructions are for advanced users that want fine tuned control over their ROM list, and want to utilize some of the advanced features. ROM Share will automatically host and setup your ROM for you in ROM Manager; all you need to do is upload the update.zip!
First, you'll then want to get yourself listed in the list of developers in ROM Manager:
Now, you'll want to describe your list of ROMs that the user sees when they click you:
And that's it! Your ROM is now listed in ROM Manager!
But, if you want to use the more advanced features of ROM Manager, such as download mirroring, and ROM customization, check out this manifest:
Note that you can do cool things that install a sequence of installation zip files. "choices" makes a user choose between several zips (use a URL of "" for no action). Only one of those choices will be installed. You can also have multiple choice selections. And "addons" lets the user choose any number of additional zips to install. You can view my manifest for a full sample.
Finally, to register your ROM for OTA updates, you need to edit your /system/build.prop in your ROM to include your Developer ID ro.modversion (as mentioned above) so ROM Manager can identify the version of your ROM. This is optional as well, but why not get OTA updates if it's just a couple lines of settings!
And that's it! Once you upload that file, your ROM will now be available to other Premium users! Good luck, and let me know if you encounter any bugs or need help!