How would you start up a social networking site?

There's no difference in a social networking web site than any other site in how it works technologically. Just a lot of web pages and the scripts to make them personalized and interactive to fit your vision. Your real challenge would be designing something with enough quality to be able to compete with the big dogs and get enough attention to make it successful.

Start out with an outline of how the pages will interact, design the pages and write the scripts to draw them. Easy to say but a lot of work, especially if you have to learn mark-up and scripting languages beforehand.

Your chances of winning the race are always better if you're the first horse out of the starting gate, not the last; but it's not impossible.

i dont no maby rob can answer