1) You need to know exactly where you are going to enter (when, why) BEFORE you open a trade. These must be clear and ironclad rules. Without discretion "because something appeared in the market", this is the way to losses. Your trading system should describe this very precise.

2) When it comes to exit, we have two ways. First, you know right from the start where you will exit (i.e. you have a set TP based on the rules of the system!). The TP MUST be set every time! If it isn't, it's like you don't have a system because you can't determine the RR!

Without knowing your RR, you have no idea if the trade will be profitable, and if the whole system will be profitable.

The second way out comes from the rules of managing your trade according to what is happening in the market. And this also has to come from the rules of the trading system you use. These rules can allow you to move the TP depending on …[system rules here]... Rules must be specific, don't act emotionally, avoid discretion.
Huge Changes, New Ideas & Decline Of Traditional Investing