That was always the fuzziest part for me when looking at the Canslim approach.. Oneil would suggest taking profits at 25%(unless it happened immediately),but then every chart in his book showed stocks going making massive returns over "long" holding periods...
I'm in the "hold winners loosely" camp, even though it's very hard for me to do. There are furious climbing stocks now that double in a couple months. DJT tripled in a month. Crazy times! One knockout can end the fight, after taking 200 little punches.
Two obvious choices are fib extensions and round hundreds / fifties. The old $100 pivot still seems to be effective, where price stops to sniff the level for a few candles, climbs above, returns, then explodes up again.
I don’t think O’Neil himself sold at 25%. Think he was mostly trading around the 10week sma. How to find & own America’s greatest opportunities
Actually, sold the put for $3.53 and bot 496 call thinking "bounce back to the highs on Friday". That one didn't work so well. I had a chance to take a double on it, but it wasn't anywhere near prior high. Win one, lose one. But winner was much bigger than loser, just like we want.