I'd argue that you can lose money buy taking profits. If you take big losers and small profits you'll eventually go broke. However, I agree with most of what you say. I usually let my trades run with a stop under the 23.6 fibonacci retracement of the current move. Since when the price breaks that point it's usually going to keep going down. I also usually don't like to lose more than 50% of my paper profits, so moving my stop loss up is a combination of that, and what my gut is saying about the movement of the market currently. My best tip for the OP is that you should define the objectives you wish for your profit taking to achieve and then design it accordingly. No set strategy will work for all traders, try what feels right for you and just keep improving it.