If your jigsaw blade is broken or accumulates corrosion over time, follow these simple steps, and change the blade with a new one:
Remove the battery from the tool.
Put your finger beneath the lever that releases the blade
Pull the lever
Shake the jigsaw gently
The edge will come out of the clamp
Insert the new blade in the clamp
Secure it tightly
Give the new blade a test run before actually working with it