Practice and Review
First remember there easy numbers which are usually 1, 2, 3, and 5. Multiply one times any number is that number, so one times 9 is nine. Multiply 2 times any number, doubles the number. Two times 3 is 6 and six is double 3. Similarly multiply 3 times anything is triple. It's usually easy to remember 3, 6, 9, 12, 15, etc. Most people can easily remember the multiples of 5 becauase the results end in either 5 or 0 (5, 10, 15, 20, 25, 30, etc.).

One easy method of remembering the more difficult multiple is to memorize some of the multiples and then add or subtract up or down to the value you're looking for. For instance, if you know that 6 times 6 is 36, than 6 x 8 is easier to remember because you add 2 x 6 or 12 to 36 to get to 48.