The flavour text hints first hints that we first need to reverse the string. This gives us:
CBLACKAREDLGREENEBLUEFYELLOWHMAGENTABCYANAWHITEYORANGETBROWNAGRAYAPURPLECINDIGOHTEALALIMEROPALLOLIVEYMOONSTONENMENTHOLDPERUAPHLOXLPISTACHIOERACKLEYTQUINCYARUSTCSAPPHIREETULIPCTOMATOHTOOLBOXOWATERE
When reversed, you may see some colour names, like black or yellow, in the string. The flavour text tells us that these are Misery Squares colours and that we need to remove these from the string, leaving us with:
CALEFHBAYTAACHARLYNDALETACECHOE
Finally, the flavour text hints at using DetoNATO's manual as well. In fact, there are five DetoNATO "letters" present in the remaining string. By removing these from the string, we get the answer to the puzzle.
CHANCE