The windscreen washer bottle is located behind the left hand service grille, if facing the front of the car.
Remove the grille by inserting the key as shown and turning it clockwise to free it. Pull the grille free from the hinges.
The cap for the washer bottle can be seen inside.
The cap is connected to a hose which unclips from the airbox by pulling it vertically.
Pull the hose so that it is out of the service area. It won't go far as there is not much slack.
Fill with a mixture of water and washer concentrate adding slightly more concentrate during the cold seasons. It really helps clear the windscreen when there is salt on the roads.