Gather balloons, flour, cornstarch, rice, or play sand, and a funnel or spoon
Stretch a balloon by inflating it and deflating it a few times
Insert a funnel into the balloon opening
Pour in the filling until the balloon is firm but still squeezable
Remove excess air from the balloon opening
Tie the balloon tightly
Use a second balloon over the first for extra strength if needed
Trim any loose balloon neck if desired
Repeat with different fillings for different textures
Check for leaks before use
Store in a cool, dry place away from sharp objects