I have found that it's much easier to hold onto a play once you have a nice profit in it. IMO at that point I determine what the minimum profit I am willing to take is and let the stock run from there. As long as I maintain the level of profit I want out of it anything else is just considered a bonus from there. I do this as I have seen way too many plays continue to run after taking profit on them. It is good to set limits on plays to keep emotion out of it but hard not to have emotion when you take profit at a set level only to see the play make huge gains afterwards.
One thing that I look at is the previous days candles. Once a run starts and I have passed my initial expectation if the stock is still running I set my sell point at half of the last green candle, if it continues to rise I readjust, if it falls to or below that point sell. That's the shortened version of it anyway, I can explain it better with a chart but don't have time right now to work one up.
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