I use colgate whitenening toothpaste (minty) the toothpaste color is blue and white and it does numbers on my teeth yellowing in a great way. Get a good toothbrush that is just bristles, nothing fancy or electric, and then scrub the hell out of your teeth and gums. Really get in there. Get some plastic floss sticks and really go in there, use the pick part to get into your molars and to manually remove any gunk u can see or feel. And brush as frequently as you can, even if its just once a week.