NB: From here on, there will be spoilers for Portal. Proceed at your own risk.

Take one (1) moderate amount of determination
With a soupçon of fear. Too much nerve makes the subject
Unpredictable.

Add two (2) long-fall boots for protection
From gravity. When the floor needs to be deadly, there are
Always acid pits.

Begin the test (Test) then introduce the portal gun
One piece at a time. Be patient, and tell the subject this
Reassuringly

After twenty (20) chambers of investigation
Congratulations! The subject is ready to bake at
One thousand Kelvin

Serve with candles and cake.