To learn or memorize a table you can just add the number into it for example if you have 2X1 then that means its only 1X2 that means two.
now if you have 2X2 that means 2+2=4.
Now if you have 2X3 that means 3X2 2+2+2 now that you know that 2+2=4 then to get 2X3 in four you would add two then your answer for 2X3 will be 6!