Here's a cut and paste from a post I put up so often. It describes the process.
"As far as technique, its simple, actually. Use the least diameter needle, usually a 5/16" 31 ga. insulin syringe, and inject into the penis midway between the head of the penis and the body, at the 9 or 3 o'clock position. A little milking motion of the penis will help
open the cavernous cavities a little, so the drug cane be deposited into the space. A little massage and the erection should begin, usually within 5 to 10 minutes, and if enough drug is injected and adsorbed, results in a penis erect for an hour or so. That's the idea goal. It can vary. Done right, with practice, the injection can and will be painless for most guys. There's no reason to think you would be any different. I don't combine by injections with other items such as pills or pump, but some here do. I, and several other guys, use what I call a pre-plump method to ensure successful injections. It begins with a penis pump, if you have one, and a penis ring. Using the pump, obtain a partial- maybe 30%- erection and apply the ring. This engorges the penis with blood,
opening the cavernous cavities and filling them with blood. Then inject into this expanded cavity. Imagine injecting into an uninflated balloon, and putting the drug into the inside, versus injecting into a partially inflated one. That's what is being accomplished with this method. When injecting, you can easily tell when the needle point enters the cavity, as the resistance will drop and the needle will feel like it has 'fallen' into it. Inject and very lightly massage the penis, the purpose is to spread the drug around and ensure optimium adsorption of the drug. Keeping the ring on for 3 or 4 minutes holds the blood (and drug) inside and lets it have the best chance of being adsorbed. Continue to gently massage the penis and the drug around for 3 to 4 minutes, then remove the ring- the blood will most likely run back out of the penis, until the erection begins. You should get the drug induced erection in 5 minutes or so. Most of us who use this method find we can use much less drug, we can control results more consistently from one time to the next and reduce the chance of priaprisms."
Also, for those who don't have a pump and rings, another method is to milk the penis, forcing some blood into it, and expanding it that way, then either use rubber bands or just grasp the base with one hand, holding the blood in, and inject with the other hand, keeping the blood trapped in the penis (and the injected drug) for 3 or 4 minutes while gently massaging and spreading out the drug.
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