Fundoshi (褌) is the most well-known Japanese traditional undergarment for men. With the arrival of Western underwear after World War II it felt out of use. Nowadays they are only used in traditional festivals (“matsuri”) and as traditional swimming suits.
Photo by Rocket news
The Japan Fundoshi Association has launched a Manga Fundoshi Kickstarter. The funding period ends at the end of this month so you still have some hours left to collaborate with the project and get your favorite manga fundoshi
In the website of the association you can find an explanation of how to put on a fundoshi step by step: