How you partial out largely depends on your strategy.
For example, partially out aggressively makes more sense with a smaller time frame strategy such as an ORB. However if you enter off of a double top or double bottom, it may make more sense to plan on a possible day trend.
Here’s an approach I have adopted that you may find useful:
Determine how time sensitive the trade is, and look for a break of higher highs and higher lows trend on the lowest time frame that makes sense.
If there is an area of major resistance, like 200 SMA / 50 SMA. Take a preemptive partial at that level when it hits. It might make sense for these partials to be a different percentage of your remaining position than the break of trend partials.
I would think of the chart as various channels of trend, and take profits either when that channel breaks or when it hits that’s resistance point. This will give you the ability to maximize profit while reducing that downside risk.