Simply push your 12oz can or 16oz of choice directly in the Trio and sip - no need to remove the gasket. With 12oz cans, be sure to insert the Artic Adapter before your can. When you're finished, pull the can straight out - no need to remove the gasket to insert or remove the can.
To convert the Trio to a leakproof tumbler, remove the gasket by turning it slightly to the left and pull up. Then, align the lid with the grooves on the Trio body, push down, and twist slightly to the right to lock it in place.