Like milky said, try to find a magic position that makes you cum fast(er). There are a few positions I avoid unless I'm going for the finish, as I know I won't last long. Girl with their legs together (front or back) is one of those. Also girl on back/legs up, me on side - easy to hit a very rapid pace for sustained period in this position, always works for me (in other positions you might lose rhythm momentarily, adjusting grip or whatever, which can kill the build up). I don't normally have a problem with cumming, but sometimes when I leave it too long using those desensitising condoms, I get to the point where I start going soft and my dick feels largely numb, and I know I'm going to have to work hard to finish. In these situations many of the usual positions will definitely not finish me off. Also, whether it's clearly faked or not, when a girl starts to orgasm and starts vibrating/shuddering down there, it triggers something and I usually follow shortly afterwards, so find a good actor
. An obvious one, but use the ultra thin condoms. I think there are sensitising gels as well you might be able to use, I've never tried these though.