"The paraglider
wing or canopy is known in aeronautical engineering as a ram-air airfoil, or
parafoil. Such wings comprise two layers of fabric which are connected to internal supporting material in such a way as to form a row of cells. By leaving most of the cells open only at the leading edge, incoming air (ram-air pressure) keeps the wing inflated, thus maintaining its shape. When inflated, the wing's cross-section has the typical teardrop
aerofoil shape." - from
http://en.wikipedia.org/wiki/Paraglider#Wing
I still need plans. Price of new canopy is about $4000 and it is way too high for me. Use of used canopy is dangerous for life so that opdion I don't even consider.