1. Create or Login to your YouTube Account. You can signup by going to: http://www.youtube.com/signup.
2. Click “Upload Videos” in the upper-right-hand corner of any YouTube page.
3. Enter as much information about your video as possible, including Title, Description, Tags, and Category. The more information you include, the easier it is for users to find your video!
4. Determine if you want your video set to Public or Private.
5. Simply click the “Upload a Video” button.
6. In the next window, click the “Browse” button to browse for the video file. Select the file you want to upload.
7. Click the “Upload Video” button.
There you have it, that’s it, seven easy steps to upload your video to YouTube.
Here is the link where you can find more details: http://www.google.com/support/youtube/bin/topic.py?topic=10524