One of the techniques used to control sexual energies in men is wearing the traditional Vedic/yogic underwear known as lungota (langota, langot, lungoti, etc. - many cultures have a similar style of traditional underwear such as the Japanese fundoshi).

The lungota is a simple loincloth that brings the sexual organ of men close to their bodies.  It keeps the sexual organ tightly controlled and prevents unwanted erections.

Also, it is a scientific fact that heat decreases the production of sperm in men.  That is why when the weather is hot, the testicles lower to bring the testes away from the heat of the body, so they can maintain their required temperature.  This is reversed when the weather is cold.  The lungota keeps the testes always close to the body heat.  This decreases the production of sperm.

These effects lower the undesirable sexual energies and bring greater control of them to the person.  The energy saved by not producing excess erections and sperm is channeled towards a person's vigor.  This leads to higher thoughts and energy, a clearer mind and greater effectiveness, etc.

The lungota does not destroy sexual energy, but channels the excess energy to higher chakras.  It even helps in directing sexual energies created by dancing the Tandava to the higher chakras, in a greater degree!

Wearing the lungota also gives other benefits such as excellent support for the groin and pelvis during yoga (innercise) and exercise.

This underwear is especially recommended for sannyasins (renunciates) and those who want to have greater control over their sexual desires and have greater vigor.  This underwear does not interfere with sexual function, so it is also recommended for married men.  The lungota should not be worn by males below the age of 12.

If women would like to wear the lungota, although they cannot benefit from the sexual control given by it, they can benefit from its support of the body and other advantages.

It is recommended that sannyasins wash their lungotas themselves.  It can be easily washed with a little detergent, and can be hung to dry from a hanger.  Dry it in a private place out of public sight.
 

Tying and Wearing the Lungota

This video demonstrates how to tie and wear the lungota:

Comfort in wearing the lungota is enhanced if you apply coconut oil over the area with hair which will be covered by the lungota.  You also can use coconut oil on hair in other parts of the body, especially under the armpits, etc.
 

Ordering a Lungota

The handmade lungota exhibited in the above video, as well as the design pattern (if you would like to sew your own), can be purchased here.

Note: We came across some more information about the lungota on this site.  Some of it seemed useful, so we have excerpted portions of it below.  We cannot verify the validity of everything stated here; however, it still seems helpful enough to include:

What is a Langota?

The Langota is a very traditional piece of Vedic clothing, worn like underwear. In India, people have been wearing this since the Vedic period (more than 5,000 years ago). All the yogis and Rishis were wearing the Langota during their yoga practice, meditation and austerity.

...

Benefits:

The pelvis area serves as the junction between the top and bottom sections of the body. When the Langota is worn and tied tightly it supports the nervous system, the spine and all the internal organs. In this way it prevents bone and organ displacement and strain on the nerves during physical exercise or yoga practice.

It enables the energy to flow correctly and in the right proportions throughout the body. The prana is concentrated so as to flow from the base chakra up to the crown chakra, due to the Langota’s tightness, instead of being dispersed through the body.

Traditionally worn to help awaken Kundalini power.

The langota helps to stop displacement of the intestines during yoga practice and heavy manual work. It helps to prevent hernias and hydrocele in men.

Provides energy, strength and stamina during exercise or yoga practise. The difference can easily be felt when practising yoga for a few weeks without wearing the Langota and then a few weeks with.

If it is worn everyday for a long period of time the temperature of the genital area is raised by one degree, in this condition sperm cannot survive easily so sperm count will decrease. However if the person wants to have a child the Langota should not be worn for the whole life. In practical life, in India, I have seen many people who have been wearing Langota for their entire life but have many children. If only worn during exercise or for up nine hours a day, it will not have any adverse effect on sperm count. In the case of existing low sperm count it should not be worn for more than three hours a day.

Contraindications:

1. In the case of aggravated eczema around the waist or in the groin the Langota should not be worn.

2. In the case of hydrocele, fluid retention in the testicles, where the size of the testicles becomes uneven, the Langota can be worn but should be tied to the comfort of the individual and both testicles must be level and balanced.

3. In the case syphilis and gonorrhea or other STDs it should not be worn.

4. In the case of hydrocele surgery, pelvic injury or surgery and fractured femur it should not be worn.

5. In the case of intestinal hernia it should be worn carefully.