They`ll make it to the exact size/shape of the template.... don`t over-analyze this [ not being flippant] ...all you need is to show them the shape/contour of your head/area to be covered ..... a couple of millimeters `here and there` won`t make a world of difference.... once you get that system out of the bag and sit it onto your head, all you`ll see is plenty of hair where there was mostly scalp ! If you want to `tidy`up your template here and there ...go ahead..just add bits of sticky tape where you think you need a `bit more`and then just trim your perimeter until you have a nice even edge.....don`t forget to mark `Front` and `Back`on it too. Once the thing is bonded on and styled, you`ll not see any minor `imperfections` which may be more obvious to you now just looking at a plastic outline sitting on your head....relax ! lol ! Paul.