Place your hands on the table.
A number is assigned to each digit. (1 through 10)



Multiply 4 x 9
-Tuck in finger number 4 (the index of your left hand).
-There are 3 fingers up on the left of finger #4.
-There are 6 digits on the right of finger #4.
-Four times nine is 36.



Multiply 6 x 9
-Tuck in digit number 6.(the thumb on your right hand).
-There are 5 fingers up on the left of number 6.
-There are 4 fingers up on the right of number 6.
-Six times nine is 54.



PS:  How to multiply  17 x 9:
(10 x 9)  +  (7 x 9) = 90 + 63 = 153