Sync keynote, GarageBand and QuickTime then upload to YouTube

I made a Keynote presentation. I also made a sound track with GarageBand, using my voice and some music loops and sound effects. I inserted the sound track into keynote. I then exported my keynote presentation to QuickTime. I then uploaded the video to YouTube, using their instructions. The presenttion sucessfully uploaded to YouTube, but the sound and slides didn't match or sync very well. How can I use keynote, GarageBand and QuickTime together and then upload it to YouTube?