Preparing HD Video for YouTube

There are a few tips and tricks you have to know to post HD video on YouTube successfully:

1. They limit the file size (1GB) and clip length (10 minutes), so if you have anything longer you will have to split it up into pieces. I recommend doing so in a user friendly way, e.g., labeling videos with the same title and "1 of 2", "2 of 2", etc. Then you can arrange your videos into a playlist just for that series and share that link for a cohesive viewing experience.
2. Limit the bit-rate, or your file size will be too big. I found that 5,000k per second is perfect.
3. Encode as h.264, because that is the native YouTube format, and will provide the best quality outcome.
4. Use your native HD resolution, my case 720p (1280x720)
5. Use best/high quality multi-pass encoding
6. Export audio at 44.1kHz stereo (optimal)
7. Optimizing for fast-start, streaming, etc may or may not help, as YouTube does post-upload processing; my testing has been inconclusive in this area.
8. These encoding options may take time, even on beefy hardware, but the result is worth the wait.
9. Remember that once you post, the video will look lo-res (bad); it takes YouTube from a few minutes to a few hours to reprocess in HD for your video to look its best. The reason they post immediately in lo-res is to at least allow you to confirm the video uploaded correctly and to allow lo-res users (the majority) access to the video immediately.
10. Also, annotations are a great and easy way to add comments and directions for users, for instance you can have an overlay with your website address.