Carmelita in Santa Catarina Barahona sits with her legs tucked under, a position that I find almost impossibe to maintain. Estela in Cabanaconde, Peru sits with her legs outstretched.
I am afraid that I can’t tell you how you SHOULD sit when you are at your loom but here are some pictures of different ways that weavers choose to position themselves.
Margarita in Huancayo, Peru sits cross legged, another position that I can't manage for any length of time. In Nebaj, Guatemala some weavers sit in a small chair which tilts back and has a back support. This looks pretty good to me.
Both these weavers in Ecuador use something against which to brace their feet which I find very effective and comfortable. Felipe is weaving a belt in Salasaca and the weaver on the right from Otavalo can be seen pushing against blocks of wood with her feet.
Here is Antonia at Convergence 2010 seated on the hard floor with her legs stretched out and perfectly comfortable.
I wove in a kneeling position at an earth Day demonstration once and was having such a good time that I forgot that normally I can’t manage this position!
Sitting on a chair like this is okay for me for a while but I find mysef wanting to push against something with my feet. It is less tiring for my back that way. I like sitting on the floor as I can have all my tools placed around me in easy reach.
Ju Nie sits on a mat on the floor, legs outstretched and braced against a large cardboard roll. I guess that in Vietnam she would have used solid trunk of bamboo against which to brace her feet.
My favorite position is on a cushion on the floor with legs stretched out and with something to brace against but each person needs to experiment and find their own way. Remember to take a break at the slightest feeling of discomfort. Walk around and stretch your legs and maybe try another position.
Backstrap Weaving 
I like to sit in a chair, too, since sitting on the floor for any length of time kills my back. For my feet, I have a medela nursing stool that I got as a gift when my son was born. They usually cost between $20-$30 USD.
By: andinell on May 14, 2012
at 12:18 am