Step 1: Buy a stapler that's not on fire, or at least, one that's not on fire when you buy it.
Step 2: Unscrew the old stapler and prepare for the new one.
Step 3: Replace the batteries with some new ones that aren't, you know, on fire.
Step 4: Assemble the new stapler using your 3rd edition of "Stapler Assembly for Dummies".
Step 5: Test the stapler on a piece of paper to ensure it's not on fire.
Step 6: Optional: Upgrade to Stapler 3.0 for extra features and better stapling techniques.