For these kind of trades, I usually use a 15-day exponential moving average (EMA) line as my trailing stop. If the stock closes below that line, I will immediately exit the trade. It's very important to trade IPOs with a stop loss and strict discipline. I've known too many people who bought an IPO for a trade, ignored their stop loss, and decided to hold onto the IPO as an investment. Many of those stocks ended up going to zero.
