You will need a strip of cloth about 9-10 inches wide by 8-9 feet long. The softer and thinner the fabric, the better. Cotton or muslin works best. Here is one of the most helpful videos I've found:
1. Let about 1/3 of the cloth fall from your waist about to your ankles. Now toss this 1/3 over one shoulder, you'll need it for steps 5-7.
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4. Now take this same length of the cloth that you just passed under and pull it back in the opposite direction (around your left hip). This will form a belt all the way around your hips; and it will finish the front pouch that contains your genitals. Pull it snug, and tuck the end of the cloth under the waistband (in back) for safekeeping. This way, all your hard work won't come unraveled while you finish the other parts of the fundoshi. We'll get back to it at step 7.
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5. Now let that first 1/3 that you tossed over one shoulder fall. It should hang in front of you like an apron, reaching down to about the top of your ankles. Draw it firmly back between your legs like you did for the very first step, right over top of the cloth that's already there. Give the fabric a twist as you go, right behind your scrotum. This will form a double layer for the front pouch of your fundoshi.
6. You should now loop the free end of the cloth in your hand around and around the part that first passed between your buttocks. When you get to the waistband, right in the middle of the small of your back, you should have roughly an equal amount of leftover cloth as you already have tucked under the left waistband from step 4. In other words, you'll loop an equal amount under the right side of the belt as you do under the left side of the belt (in step 7).
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Clear as mud? Are you a visual person? Try this step-by step diagram: http://fundoshi-lover.blogspot.com/2007/04/blog-post.html
A few tips:
- It's a good idea to keep things snug and tight as you go.
- Practicing is actually fun, don't worry if it takes a while to get it right. Use a mirror to help you follow the steps.
- It can be fun to practice with another person, and to help each other.
- Silk doesn't work -- not grippy enough.
- A well-tied fundoshi will stay on no matter what, until you untie it, even if you're swimming or being active.
- Look at pictures and diagrams to help you get the shape right.
- There are hundreds of regional variations on how to tie fundoshi, mine is just one simple way to tie rokushaku-style -- so feel free to experiment and find what looks best and is most comfortable for you.
Now you try! Here's a different video, of the "Fundoshi Prince" tying on both an etchū and a rokushaku fundoshi. It's from some sort of light-hearted Japanese variety show. Just ignore the laugh track and the music by Wham! (maybe put on Brian Eno's "Music For Airports" instead?) and prepare for take-off in your new, expertly-tied fundoshi!