This is how you customize a 40oz tumbler. Start with a design that can be broken into 2 pieces. Ideally there is some white in the middle so you don't see a Ravenscroft Essentials Ultimate BYO Glasses Bag Ravenscroft Crystal 1950s Colorama Aluminum Glasses and Mugs. I remember these from my childhood, I can still taste the metal. Hanging Glass Rack 4 Channel Polished Stainless Steel Vogue Silicone Wine Glasses Unbreakable Clear Rubber Drinkware for Camping and Outdoor Use Reusable Silicone Beer Cups How to Pick the Perfect Wineglass