After a very long time trying to figure out how to get the plug out of the exercise ball without popping it or ruining the plug…..this is the easiest way:
Use a 1 inch long binder clip
Then, use tweezers or something similar to slide under and pull straight up (caution if using scissors)
Plug hole with finger and use a large pump with a cone shaped adapter (also suitable)to fill up the ball (the cylinder adapter does not work and the basketball adapter gets permanently jammed into the ball. This is too small also.).