Method of adjusting a cushion with segments 14c, 14d, each having a foam core 22c’, 22d’’ and flexible cover 24c’, 24d’’, where a valve 20 permits air into and out of the core 22c’, 22d’’； and involves opening all valves 20, applying pressure to a segment 14d to be adjusted, then either expelling half of the air in the core 22d’’ or limiting expansion of the core 22d’’ to half capacity, and sealing all the valves 20. The pressure may be a user sitting on the cushion. Multiple segments 14c, 14d may have restricted expansion, which may be 30% of capacity. Also disclosed is a foam cushion having segments 14c, 14d on a base 12 where air is selectively allowed into the core 22c’, 22d’’ via passive intake so that the cushion is self inflatable. A secondary wall 26d’’ may be between the cover 24d’’ and core 22d’’ for use when the cover 24d’’ is damaged. Segments 14c, 14d may be fluidly connected.
