re: Poker & Ring game profit
Pretty much how good ole JD said. If you feel comfortable, stay and set a stop loss. Whatever you feel comfortable with. Although, with you asking such a question I have to assume you don't feel comfortable with staying.
I myself, usually leave once I double my buyin. Though I play for profit and usually buy in at the max, I think it goes for you too. No sense in risking that hard earned profit on a tilt play or misread.
Maybe leave your seat on the table to start the reset timer, take a 30 minute break, then buy back in at a comfortable amount and continue your complete ownage of those donks.