You sell at 750 [...] But then, you wake up and price is 850 and you feel suicidal.
If you get suicidal at 850 after selling at 750... maybe trading isn't for you? I mean, here you didn't even lose any money -- you get suicidal because you didn't make any money.
What do you do when you actually lose money?
And by "lose," I mean lose more than ~15% of your stake, which is what we're talking about here?