On your own - I have heard good things about fleshlights and other masturbation sleeves that allow one to re-learn how to orgasm using less intense sensations.
If you have a sexy lady friend, I recommend hand jobs with prolonged orgasm denial. Meaning over a few days or hours, she helps you build to several "peaks" (varying levels, but up to an 8 or 9 on the "omg, I'm gonna cum" scale) before finally allowing a release at irregular intervals. I've also found teasing and working another erogenous zone, like biting the nipples, weight or temp play with the balls, helps break the pattern of cock>hard>stroke>cum. Which, no matter the method, is a mindset you have to be willing to part with.