From part one of a two part article on Tantric sex in a South African publication called Women24, this handy tip for delaying male ejaculation:

At the point where you feel you might be reaching your peak, press your tongue against the top of your palate. “By tensing muscles in your mouth, you move blood away from your groin, giving you a chance to recover,” Sampson says. “Don’t feel embarrassed, though – it’s unlikely to cause too much of a distraction for your partner.”

From part two, instructions for the Thrust of the Phoenix:

Perhaps the most widely known tantric technique, this little winner can be used with any position. When you start thrusting, go in shallow (around two centimetres) for nine strokes, then one deep, then eight shallow, then one deep, working your way down to one shallow. “This has been known to give women who claim to never orgasm their first taste of the big ‘O’,” says Johnson. “Building slowly up to a big crescendo will have her willing you to reach the climax.”