Ahhhh the age old how to exit thread.
There's some floating around TL so make sure to do a search.
Here's the best piece of advice I can provide - as soon as you realize AND accept that you will NEVER get out at the best optimal price, you can start to craft your exit strategy. Neither of you are there yet.
Here's what I mean - when you are saying 'only if...' it tells me that you want to catch the monster moves AND get out when there's only a little profit available. Well, that's next to impossible. You have to decide if you are either:
1) Going for the large moves and will make little/nothing on the small moves
2) Looking to take realistic profits every trade
I don't see how you can do either consistently. In a nutshell, it's a question of trying to hit homers or singles. I would suggest sticking with the singles in the beginning.
I realize that some may say it's possible to do both based on XYZ or ABC or maybe some of ABC mixed with XYZ and sprinkled with 123. And maybe it can be done. But in the beginning especially, I would suggest finding one method of exiting that suits you and then work it. I personally like taking regular profits, but I mainly daytrade. I've also found in my personal trading that many times going for the larger moves and taking small gains/losses on the other trades that I make LESS by going for MORE and risk MORE to do that.
That will open up your eyes real quick.