This technique can be mastered after working one or two examples, and is probably the easiest technique for squaring numbers with just 1s such as 111, 1111, 11111, and so forth. Squaring a number means to multiply the number to itself. For example, squaring 1111 means to multiply 1111 by 1111. By standard math methodologies, multiplication is performed and starts from right to left one digit of the bottom (or right) number at a time.
So how would you square numbers with only 1s? Multiplication is not even necessary using this technique.