1. Square the last digit (keep the carry)   _ _ _ X
2. Multiply the last digit by 10, add the carry   _ _ X _
3. The first digits will be 25 plus the carry:   X X _ _

   Example:

     If the number to be squared is 53:

1. Square the last digit (keep the carry):
       3 × 3 = 9 (keep 3)     _ _ _ 9
2. Multiply the last digit by 10, add the carry:
       10 × 3 = 30 (keep 3)    _ _ 0 _
3. The first digits will be 25 plus the carry:
       25 (+ carry): 25 + 3 = 28    2 8 _ _
4. So 53 × 53 = 2809.

   See the pattern?

     If the number to be squared is 56:

1. Square the last digit (keep the carry):
       6 × 6 = 36 (keep 3)     _ _ _ 6
2. Multiply the last digit by 10, add the carry:
       10 × 6 = 60, 60 + 3 = 63    _ _ 3 _
3. The first digits will be 25 plus the carry:
       25 (+ carry): 25 + 6 = 31  3 1 _ _
4. So 53 × 53 = 3136.

Practice and you will soon be producing these products quickly and accurately.