One of the biggest obstacles to making the kind of progress most people aim for in their lives - whether in their careers, their relationships, or their own emotional, physical, and/or spiritual growth - is the poisonous negativity they aim at themselves with much greater frequency and intensity than they may realize. The negativity is so deeply embedded in many people that it almost ceases to be visible to them.
Perhaps you think you may not have this problem, or if you do that it's a relatively minor one. Because of its invisibility you're probably underestimating the extent to which the negative self talk is holding you back.
Most guidance related to countering the destructive effects of this habit (because it is truly a habit, a deeply engrained response to adverse circumstances) focuses on cognitive techniques. Examining whether the self talk is stemming from an unproven assumption ("I'll bet the interview is going to be a bear"), or from overgeneralizing ("I always do stupid things like that") or from comparisons with others ("She's so much prettier than I am"), or from all-or-nothing thinking (I can't believe I didn't know the answer to my boss's question, I never get things right) etc. The problem I have with this advice is that it doesn't really get at that deeply engrained underlying habit. It's too logical, if you will. Breaking a pattern with such a strong grip requires an approach that will create a more jolting response.
A technique that I've recommended to a number of clients is one whose source is unclear (although both Tony Teegarden, a business advisor, and Jacob Glass, a spiritual mentor, have spoken about it prominently) but whose results are very positive. The technique is to imagine that instead of the negative statements being addressed to you, that they are addressed to your five-year-old child (whether or not you actually have a five-year-old is irrelevant; we can all imagine what the impact would be). So, just think about what it would do to a little tyke if you berated him with statements like "You're so stupid" or "You always mess things up" or "You really look horrible today." What would that constant torrent of criticism do to the child's self-esteem? In what way could that possibly help the child's performance?
This technique doesn't require you to frequently catch yourself indulging in that negative self-talk, as do the cognitive solutions. It just asks you to think about how corrosive and destructive such talk can be by imagining it being addressed to a little kid. In most cases, the inner sense of compassion we almost all have for children will kick into gear and help loosen the hold of this nasty habit.