To be good, you must perform such acts as "good deeds" and such. to get easy goodpoints, you may -Eat certain foods -Donate to temple of light -Have sex with a condom -give beggars money It all affects your morality.... ....We are talking about Fable II right?
See Also: Become good from evil
In Fable and TLC you must do similar things to those above. In addition, you get good points for killing all 'evil' enemies, like bandits, hobbes and undead. You can also donate to Avo.