Personally, while I was younger and was masturbating (i started around 8, before I even knew what an orgasm was and nothing ever came out) later I started to worry because I was so young and never had anyone teach me about sexual things, and would usually orgasm anywhere from 30seconds to 3minutes afterwards, I looked up on it around the age of 14, ive found some pretty bizzare ways of actually strengthing the muscles that cause the orgasm.
It worked so well for me because I had done it for easily a year or two just because I was afraid of my reaching climax so soon, seeing alot of things about it in movies and how embarassing it was I never wanted to go through it myself, now it takes me so long to reach climax reguardless of how aroused I am I can usually pleasure my girlfriend 5-8 times in a row without stopping before I cum even once, it feels so good to be able to make her happy like that and she gets so loud and turns me on so much youd think id be insane not having to orgasm, now I can go anywhere between 30min to 2 hours without cumming, it may seem bizare to try these things but the musles that cause the orgasm are just that, musles and how do you make any muscle stronger? By working it out! And if you know how to tense yourself up itl only make it easier, which, btw, every guy should know what I mean by that, clenching the muscles which usually cause the penis to jerk up or twitch lightly
if at first you feel your penis is to weak try staying hard, getting your self close to orgasm, not quite cumming, but staying there, right at the edge of orgasm, try to do it as long as you can, but dont hold it in so much to where it restricts sperm movement! That can cause a backup in the prostate and give you an infection.
Another way to do it, take a washrag, wet it some so it has some weight on it, stand in the bathroom, or in your room, whereever you can be alone for at leats 10min without anyone bothering you, rest it over your erect penis, and clench your musles over and over, basily causing your penis to work harder to lift itself, since your using the muscles to actualyl cause your penis to jerk up, do it over and over, short time periods at first, maybe 5min starting would work fine, then the more you do it the easier itl get and start using heavier cloth to rest over yourself, since you have to constantly work your penis not to allow the cloth to fall off while still jerking it up by tensing your muscles itl work them better, I know it sounds completely weird, but its worked for me, so well I dont have to worry about it at all anymore, even while getting a blowjob (which my gf is wild at) I can last 15min easy, hope that helps you, nobody should have to worry about premature ejactulation
oh yea, and with this method, you -cant- use your hands to help hold the cloth on -or- move your penis manually