Saying Goodbye to Leo

How do I say goodbye to Leo, the 4 year old pit bull we rescued only 6 months ago. How do I say goodbye to a beautiful, majestic, affectionate, animal who Annie and I have become so attached to in such a short time. Leo has a large tumor, an aggressive cancer, predominately in his shoulder. The doctors can do nothing for him and the prognosis is such that we have no choice but to euthanize hm tomorrow. This muscular, athletic beast can no longer walk normally, limps in pain and stops to lay down every several steps. Yet he manages to walk into the dining room and sit under our dinner table every night. Tonight is his last night and I don’t know how to say goodbye. I wish I could know if he realizes how much we love him and will miss him. Goodbye, my friend. Rest in peace, free of pain.