Assuming that you don't want to go to a professional therapist, what can you do to help yourself if you're a man who experiences premature ejaculation during sex? The answer is to use one of the powerful and effective self-help programs available on the web to deal with the problem, so you get more self control and you're able to last longer during sex. First, though, it's useful to understand that "control" is the wrong way to look at ending premature ejaculation, because control implies that you have to struggle against premature ejaculation. The natural way to enjoy sex, in fact, is to choose when to ejaculate, so that self-control is not an issue. It should be your choice when you ejaculate, your choice how long sex lasts.
This may seem unimaginable to you right now if you worry about premature ejaculation every time you enjoy sex. You may question how it could ever be possible for a man to be able to decide when he ejaculates. But think of urinating - you make a choice about when you do that. And that is how it should actually be with your ejaculation - and the reality is, you can easily learn to control when to let go and ejaculate during sex. The thing is that men who ejaculate too soon are too sensitive to sexual stimuli, too sensitive to sexual arousal - they get to the point of no return, otherwise known as the point of ejaculatory inevitability, too soon, and often without even knowing they are getting there. Then, before they know it, their ejaculation happens prematurely once again, reinforcing the cycle of self-doubt and anxiety.
If you can stay below the point of ejaculatory inevitability, in other words if you keep your level of sexual arousal below the critical level, you won't ejaculate until you wish to do so - and you can make that choice by starting to thrust harder and faster and building up to a powerful orgasm when you're ready to to so. That might be when your partner has enjoyed her orgasm, or when you're both happy with the time you've spent enjoying sex. But the key thing is that you choose when to ejaculate. You don't experience a rapid ejaculation, coming before you and your partner want it to happen.
I should add at this point that remedies for premature ejaculation based on contracting your PC muscles to prevent yourself ejaculating (also known as your love muscles) simply don't work. You can't contract those muscles strongly enough to stop yourself ejaculating - and trying to do so spoils all the fun of lovemaking, which is all about enjoying sex in an easy way, and deciding when to ejaculate, not struggling pointlessly against the power of your own body, as it tries to make you ejaculate too soon!
So the essence of any technique to overcome rapid ejaculation has to be identifying the moment just before you ejaculate, and then letting your sexual arousal fall until you are not going to ejaculate. You can do this by ceasing your thrusts and remaining still inside your partner until your level of arousal has dropped. You can even pull out altogether. But timing this is crucial. When you feel you're back in charge, so to speak, and the feeling of an impending premature ejaculation has passed, you can carry on enjoying intercourse.
Stopping premature ejaculation like this requires some self-discipline, because the temptation to simply continue thrusting and enjoy your orgasm and ejaculation is strong! So you start by changing your attitude so that you have a strong wish to last longer during sex and a firm belief that you can stop your premature ejaculation!
Of course, you can learn how near you are to the point of no return, just before ejaculation, during masturbation. Often men self-pleasure quickly and ejaculate as soon as possible: instead, it's helpful to develop more control over how soon you reach orgasm and ejaculate. When you sense your orgasm and ejaculation is approaching, you stop masturbating and wait until you feel that the moment of incipient ejaculation has passed. Then you can start to masturbate again.
Very quickly you become much more sensitive to the point at which you're going to ejaculate. The signals that precede your ejaculation, rapid ejaculation or otherwise, can include tension in your legs and groin, a tight feeling in your testes (balls) and a tingling sensation in your penis. But whatever the clues are for you that you're about to enjoy your sexual climax, focus on them until you have a good sense of how near to ejaculation you are.
In this method of learning to control premature ejaculation you approach ejaculation and then stop what you are doing. Soon, you'll feel more confident that your sexual arousal has dropped and you'll be able to maintain yourself on the edge of ejaculation for increasing periods of time. This will also make your orgasm much more powerful when it does occur.
You might also wish to train your your so-called love muscles, or PC muscles, as part of your program to overcome rapid ejaculation. When they are fit, they contract more powerfully during your ejaculation: this adds to the strength of your orgasm. That muscle fitness also gives you greater control over the timing of your ejaculation - not by clamping them down and stopping your ejaculation, but simply by giving you more power and choice about when you ejaculate. Your PC muscles can be strengthened with "Kegel exercises for men" (research this on the internet for more details); you can identify them fairly easily by contracting them when your penis is erect. If you strengthen your PC muscles you will ejaculate harder and have more enjoyable orgasms.
As you may have realized, the last stages of your program to overcome premature ejaculation involve trying this new found self-control as you enjoy sexual intercourse. If you feel you are about to ejaculate, pause until your level of sexual arousal has dropped, then carry on making love when you feel more in control.
The most important thing is that you know when you are about to ejaculate and you then act to stop it happening! You can stop ejaculation by paying attention to how aroused you're feeling, not to how exciting it is to be making love, or what your partner is doing, or how great it is to be having sex: you simply focus on what you are feeling, on the signals (as we described above) - and if it's going to happen, you stop thrusting until your sexual arousal has dropped again and things are under control once again.
You can repeat this procedure as often as you need until you have gained greater control over your ejaculation. There are of course, other things you can do to control premature ejaculation, such as enjoying sex in those sex positions where your penis is less stimulated, so that you will last longer - side by side sex is very good in that way.
The outline given above is just a summary of the full self-help treatment program for premature ejaculation, which is explained in great detail on the website Prevent Premature Ejaculation , where you can also find details of other techniques to help yourself overcome premature ejaculation, like self-hypnosis.
Finally, if you happen to have the opposite problem and you are a man who has trouble ejaculating during sex, see Stop Delayed Ejaculation!

