Please contact the end customer promptly, best by e-mail, and offer him a consultation on site (even a welcome coffee or sparkling wine with your personal consultation). A nice touch could also be to include a picture from your showroom. The aim must now be to attract the end customer to your shop. Here you should not be too intrusive, but prompt and personal. If the end customer does not contact you, you should follow up after about 3-4 days by e-mail or by phone.