How do I transfer Borderlands 2 game save files onto another account or computer?
Borderlands 2 savegames are stored in
Windows:
C:\Users\[user]\Documents\My Games\Borderlands 2\WillowGame\SaveData\__numerical_id__\
Mac:
~/Library/Application Support/Borderlands 2/WillowGame/SaveData/__numerical_id__/
Just copy the folder from one Computer to the other.