Your aim should be to make math fun for your child and help them gain a solid understanding of the basics. Encourage your child to incorporate math into their daily activities, help them do mathematics worksheets, and then use the lessons therein to create fun activities for your child. The secret to learning math is to have an open mind about it. Just because you hated math doesn't mean your child should, and you will be doing them a disservice if you pass your negative feelings on to them. Make learning math fun, get a comprehensive set of mathematics worksheets to make it exciting and stimulating, and encourage your child's efforts all the way. Every math genius had to start with 1 + 1, just like your child.
There are many math_based games available in educational toy stores that will help to reinforce the principles your child learns in worksheets. Computer games can help too, but depending on the age of your child, it is best not to encourage too much computer use at an early age. Everyday activities can be turned into math lessons too. A trip to the grocery store can turn into a math lesson if you encourage your child to help you count how many items you are buying, or add up the bottles of milk as you add them to your cart.