The pillow has an obvious "top" and "bottom", the "top" side being noted by the presence of the small Eagle Creek logo. On the "bottom" side (which rests against your chest when you wear it around your neck) is a large black flip-lid the size of a half dollar coin. You pull the flip-lid open and simply blow into the pillow two or three times to inflate it; a one-way rubber flap prevents the air from escaping, and the flip lid closes shut over it to complete the seal. To deflate the pillow, open the flip lid and push a finger against the flap to let the air out, massaging the pillow to get it all out.