The “soft entry” technique avoids all performance demands. It is also useful if a partner’s penis is uncomfortably large, as it gives the vagina a chance to relax and adapt.

Note: We do not recommend the following instructions for anyone with long fingernails. So, you may have to improvise.

“Soft entry” step-by-step
  1. One of you lubricates both partners’ genitals
  2. If the man is not circumcised, the woman gently rolls back his foreskin, exposing the head of his penis.
  3. Next, with two fingers of her non-dominant hand she gently, firmly grasps the root of the penis. Then with two fingers of her dominant hand, she grasps the head of the penis just behind the rim.
  4. She pulls the penis gently toward her and inserts the head, gradually feeding the rest of the penis into her relaxed vagina.
  5. She takes care to maintain snug genital contact by wrapping her legs around him, so the penis stays put. (Giggling allowed if it doesn’t stay put at first.)
  6. Both partners relax and focus on what they feel in their genitals. Wordless sounds of contentment and pleasure work well to communicate feelings.

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[From Tantric Sex for Men: Making Love a Meditation by Diana and Michael Richardson]
Soft Penetration–Entry Without Erection

Soft entry is a pure and simple alternative when there is no erection. It completely eliminates the pressure of having to have an erection in order to have sex. Given the general lack of stimulation [in Synergy-style sex], not having an erection is quite normal and nothing to be concerned about. Soft entry actually bypasses many erection concerns and issues, and gives us a humble, human way to get our bodies together. The advantage of a soft start is that both man and woman begin at zero, so to speak, allowing their temperatures to warm up together. Soft entry is very easy and with practice, can happen in the flash of a second. There are two possibilities: man puts his penis inside woman, or woman puts the penis inside her. We recommend the second option. …

The first few times soft penetration is tried, most men will find that they do not “feel” much in their penises. This is very common and will change as soon as the penis adjusts to a new way of being used and perceived by man. This insensitivity is due to a long history of stimulation, so for it to be a little numb is not really surprising. The way to retrieve sensitivity is to relax into woman, spend as much time inside her as possible, and take full consciousness down into your penis….Gradually sensitivity will return. …

Spontaneous erection within the vagina is not something that can be expected or demanded of the body. It is a by-product of a special constellation of factors, among which are awareness, presence, relaxation, and love.