My skin is now clear, and the dark spots left behind by some of my acne is gone. It takes time for the skin to heal, but anything moisturizing should help. Make sure you are drinking enough water, because hydrated skin can regenerate quicker than thirsty skin. As for topics you could put on your skin, I would recommend Clinique's dark spot corrector, and Ponds cold cream.
The dark spot corrector really does make a difference in the dark spots on your skin, but you have to make sure you are consistent with use. The ponds cold cream is just another added moisturizing face wash, but if you have a lotion you could use that as well.
I used Kojic acid soap to lighten my marks. It's very effective, but I warn you that it's very drying. Use a high quality moisturizer to combat the dryness. It will also lighten your skin alot, so if you don't want to get lighter, just spot treat your marks with Kojic acid.
Leave it on for 2 minutes MAX; if you leave it longer than that you might induce a chemical burn. Most importantly, use a sunscreen during the day to prevent any existing marks to further darken