Using this tumbler is easy. Just open the lid and pour in your favorite hot or cold drink. The tumbler is great for taking with you on hikes, to the office, or just around town. When filling it with hot water, be careful as the steam might lift the lid. It's not a problem, but you can hold the lid gently while pouring. To keep it in good condition, wash it regularly with mild soap and warm water. Don't use abrasive cleaners as they can scratch the surface. Also, make sure to dry it thoroughly before storing it to prevent rusting.