Remove the PVC cap found at the bottom of the bottom sash, here you’d find your first fixing point. The purpose of the cap is to cover up any fixing points. Now slide up the bottom sash, tilt it slightly and then slide it as high as it’ll go. By doing so, you should be able to reach the middle section of the side frame. The second fixing point is just below the shoe as illustrated. When the sash is in working position, this screw will be hidden. Remove the top corner cap and you will find your third fixing point. When both corner caps have been removed you’ll also be able to remove the top board allowing you to fix the window anywhere along the top section too.