As I mentioned up-thread, I'm mainly doing this to gift the shares to kids and grandkid. I figure it's a way to get them more interested in investing and watch one of the most interesting companies in our lifetimes.
it depends on the price action in the first hour or two. I’ll short when it stalls, when it breaks below 1-minute VWAP. With the Facebook IPO I shorted about 10 AM, but each one is unique. I usually avoid IPOs altogether unless there is excessive hype. This one certainly qualifies.