I'm guessing you've never used the command-line at all?
If that's the case, then here are my easy step-by-step instructions for total Terminal newbies.
- Get 2 folders open in the Finder: the folder where you have unzipped KindleGen, and the folder where the html or ePub file you want to convert is.
- Go to Applications/Utilities and launch the Terminal app.
- Drag and drop the KindleGen utility from the KindleGen folder onto the Terminal window: you should see a line then saying /WhereverYouvePlacedIt/kindlegen show up in the Terminal window.
- Drag and drop your OPF or ePub file if you have one or your HTML file if that's all you have, onto the Terminal window: you should see a line then saying /WhereverYouvePlacedIt/yourfile.opf.epub.html right after the "kindlegen" bit (with a space)
- Type "-o WhateverYouWantToNameIt.mobi" right after the kindlegen + file.opf.epub.html stuff. Optionally add "-c2" for tightest compression if file size matters.
- Press return, and wait for KindleGen to compile your book or spit out error messages (add "-verbose" to the command line options when you retry to see more error message which may help you track down the problem).
- If all goes well, enjoy your new e-book!
You may find it easier to use MR member pdurrant's handy drag and drop
AppleScript front-end to KindleGen, although I don't know if he's updated it for the changes in 1.2.
Also, the newer versions of KindleGen bloat up the resulting file by incorporating a copy of the original source files in the final book, so you may also want to use
KindleStrip, which also has a handy AppleScript droplet version, to get rid of that before you submit the file to Amazon.
If you get more proficient at using the Terminal in the future, you can add both commands to a location in your $PATH somewhere and alias them for the most usual options you use for convenience.
Hope this helps.