I bought her scallops ruler. There are instructions in the pkg. If you don't have the ruler just measure the length of your quilt & divide that number ie: 60" long, 60 divided by 6 will give you 10 scallops that are 6" apart, 60 divided by 7.5 will give you 8 scallops that will be 7.5" apart, do the same with the width.