La Tenda PVC curtains need some time and especially heat to hang out 100% straight. When it is hot and sunny outside, this process will be completed much faster than when a door curtain is purchased in a colder month. You can speed up this process of straigthen the curtain, dividing it in two halves, into two bundles tied together. The lower 1½ meters of each bundle then heath up about 10 minutes with hot air from a hair dryer or hot-air gun. The heat makes the strings smooth to help gravity a little making them become straight.
Caution: The heat source is not to be hold too long in one place, because otherwise the PVC cords can melt.