Mix up ranch dressing mix, mayo, and sugar. Set aside. Layer all ingredients: lettuce, cucumber, green bell pepper, celery, and green onions. Top with dollops of dressing and spread over veggies. Sprinkle with cheese and bacon bits. * Refrigerate at least 3 hours to overnight. I serve mine in a 13 x 9 casserole dish. You can get a little fancy with a trifle dish if you'd like. I just find it easier to serve in 13 x 9 dish.