Keyboard:
Space to add another
Controller:
X to add another
Y to add a ton more
A to bring to cursor
B to delete
Left Analog Stick to move cursor
D-pad up and right to turn elasticity up
D-pad down and left to turn elasticity down
Mouse:
click (and hold) to bring to cursor
Touch:
drag slider bar for elasticity
tap spawn to add another
touch to bring to cursor