Go do 100 bad things to one person --- don't greet them, borrow their stuff without returning, invade their personal space... and so on
After you do all that, go do one good thing to that same person --- defend them in a physical fight, provide emotional support through a difficult time.
See how that person will react. Chances are, they'll remember that one good deed and forgive you for your numerous other transgressions.
Go do 100 bad things to one person --- don't greet them, borrow their stuff without returning, invade their personal space ... and so on
After you do all that, go do one good thing to that same person --- defend them in a physical fight, provide emotional support through a difficult time.
See how that person will react. Chances are, they'll remember that one good deed and forgive you for your numerous other transgressions.