An expanded orgasm extends beyond the genitals. You feel it in your groin, perhaps your buttocks or thighs. It lasts longer and stretches further than the average orgasm (not that there is anything wrong with the average orgasm).
First, practice lengthening and stretching your orgasm while masturbating, either alone or together.
Masturbate without ejaculating for as long as you can by stopping or changing strokes when ejaculation is imminent. Count the contractions you experience when you ejaculate—normally between three and eight. Next time you masturbate, try to delay ejaculation longer. With practice, you will increase the number of contractions you feel.
Masturbate. As soon as you become highly aroused, use the other hand to massage with light, shallow strokes the area of the vulva, inner thighs, and groin. Imagine that you are spreading your orgasm throughout those areas. Continue the massage throughout your orgasm.
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