Once you have introduced quantities to your little one, you can move on to adding and subtracting and then get into some multiplication and division. Many parents teach their baby math using red dot cards. These can be purchased in a math kit from IAHP.org or you can do math with your baby right through your computer with a program called Little Math. Either one of these methods are excellent for teaching babies math.
In order to teach multiplication and division you just manipulate the quantities you have taught your baby to teach facts. For example, you can take your dots for six and your dots for four and tell your baby that six times four equals and then you show them the quantity for twenty-four.
You do the same thing to teach division. All that is required is to spend two weeks on each subject. Work on addition for two weeks, subtraction for two weeks, multiplication for two weeks and two more weeks for division. You should show your child a different equation each time. You are not trying to drill a particular fact into their head, you are just guiding them to understand how each of these properties of math work and they figure this out on their own.
If you need more guidance and information you should read How to Teach Your Baby Math by Glenn Doman.