get links to them. most youtube videos that you see appearing in the serps have been viewed a lot of times and people linked to them
Most important for those videos is linkbacks, the more people that link to your video, the better you will be in SERPs. Also, good keywords and a great description will also help.
Actually that process is what you call SMO.. using videos or pics to promote a sites... Optimizing a site with the help of articles with videos attached...
Promoting youtube is like digg promotion. You need to get MANY friends within Youtube and share share your videos with them. Thats's all
keep uploading video daily, therefore it can increase subscriber to your channel. Moreover, make sure you put the watermark on the video and it much better to upload a new homemade video.
Make your own video and put your URL on it... I got 178K views of my site through one of my videos, and 76 link backs..