On backpacking-lite I found some good informations how to make the corners: http://www.backpacking-lite.co.uk/diy/make-an-ultralight-tent-bathtub-floor.html
amarok.live
"The true harvest of my daily life is somewhat intangible and indescribable as the tints of morning or evening. It is a little star-dust caught, a segment of rainbow which I have clutched." (Henry David Thoreau, 1854)
amarok.live 
Happy sewing Olav,
Have you got a sewing machine yet?
I use a Elna Elnita that I picked up for $25 at a Thrift shop.
http://www.2hand-dd.com/pong/pj/elnita150-1.htm
Great machine.
Ron
hi ron :)
barbara has one, but i haven’t seen yet. i plan to use this stuff : http://www.extremtextil.de/catalog/Ripstop-Nylon-Zeltstoff-silikonbeschichtet-65-g-qm-2-Wahl::1197.html
greetings