Say that you fail to make a sale that you thought was going to happen or get rejected by a gallery where you really wanted to show. There’s a particular tactic you can employ to put this unfortunate (but not uncommon) incident behind you.
That’s to “get a grip on your mind”—that is, you need to actively think thoughts that serve you rather than allow yourself the “indulgence” of brooding about this incident. You do this getting a grip by “hearing” the pestering thought and saying, internally or out loud, “No, you aren’t serving me!”
You actively dispute the thought and refuse to indulge it. Then you substitute a thought that does serve you, for instance “I have a long, great career ahead of me!” This three-step process of hearing, disputing, and substituting is key to maintaining your emotional health and succeeding at your chosen career!