I suppose you have to know just what great things you wish to accomplish. Just remember that if you wish to accomplish material greatness i.e. fast cars, lots of money and large homes then you will not be able to take these with you when you die.
If you wish to accomplish spiritual greatness, then love your neighbor, feed the hungry,
give comfort to the down hearted and serve your fellow men to the best of your ability.
Where your heart is so will be your reward.