Restringing day night shade..help

I bought the kit but the strings were not long enough for my long window. Had to do it again. I used 90# test dacon fish line, it was strong enough but too slippery. At the campground a friend had some contractor string, we used that (boy it went fast with three pair of hands). This is working. It slowly works it way down, but it is very slow and livable.
I should have purchased real restringing cord at Joanns, right Off the bat.
BTW drawing a diagram of the stringing pattern as I took the other one down, was extremely useful.
Mike Leslie