Here i have a short skirt with a broken zip ,instead of throwing it away..a surefast way to repair it ..what you will need ..1..a punch plier [buy from ebay ]  ..2 ..Brass eyelets ...3 , a pair of sharp scissors ..4 a pair of Tights , Thick Black Opaque are the Best to use ..ok first take the punch pliers and punch holes each side of the zip , no need to take off the broken zip , now insert the brass eyelets , again using punch pliers , now take the Tights and cut off the waistband as i did or you can choose to cut lengthways along the leg a strip of nylon ..roll the nylon strip and thread it through the holes as you would with shoelaces on a pair of shoes , pull tight and wrap the remaining nylon thread around your waist like a belt ..you can also do this with jeans , trousers that have broken zips .