Install the curtain rod brackets to run underneath the counter. You can attach the rod to the front of the counter or the underside of the counter. Mine is installed on the underside.
Cut the shower curtain to the right length, allowing 1 1/2” extra for hemming. Hem the curtain top and bottom – either sew it or use iron-on hemming tape. Allow a ¾” hem at the top for sliding onto your curtain rod. Hang the curtain on the rod. If you prefer, you can use clip on curtain rings and save yourself the hemming duty. Just fold the shower curtain to the right length and clip it onto the rod.