learning to draw can certianly be learnt, yes theres a natural talent to it but it can still be learned to a degree.
there are alot of books that can be bought about illustrations and drawing clothes.
do you want to draw the clothes on models or more working drawings of your designs?
"It is the unseen, unforgettable, ultimate accessory of fashion. that heralds your arrival and prolongs your departure." - Coco Chanel