Most people seem to DCA. When to sell?

I’m wondering if it’s a good idea to sell a few shares every time the price pops up a certain percentage.

Something like let’s say someone has approx 100 shares. Plan to sell 2 shares every time the price goes up 25%. If it keeps going up, sell another 3 shares up another 25%. Keep the cash or invest in SPY while waiting for a drop.

And every time it drops a certain percentage maybe buy 3 or 4 or 10 shares or something.

Would that work?