You sure can be a "good" person without believing in God, or anything else for that matter. It is important to make the distinction between "God" and "religion". God DOES exist and everything made by God (including people) is already good (many people choose not to DO good things, but you are not "defective", you are already GOOD, CASE CLOSED.
YOU ARE A GOOD PERSON.
Religions don't necessarily want you to believe that. They want you to fulfill their requirements, obey THEIR laws and be "AS THEY WISH". They use guilt to intimidate you into being a member of their "club". God is NOT a religion. They will also tell you that they have priests that can forgive sin (wrong-doing), that is not true. The last time there were priests that could forgive sin was in ancient times when the "Levitical priesthood" was ordained by the Creator to do so (the third book of the bible, "Leviticus", was their guidebook). Sin has nothing to do with being a good person or a bad person (of course, people who DO bad things sin more than people who make a habit out of DOING good things). There are a lot of popular sayings like "Remeber the Bismarck" or "Remember Pearl Harbor", but none like...
Remember the Creator
so, that you have decided to remember the creator and be mindful of Him, well, how would you feel if someone decided to remember you and be mindful of you? I imagine right now, that if the Creator were human, He'd be blushing, good person.