Breaking a Serial Monitor Decimal Number down into components?

OK, now I am able to get the exact integer value from what I input into the serial monitor! However, I'm still having trouble breaking a multiple digit integer number like 123 into its components 1, 2, and 3 to display properly on the multi-segment display.

It seems as though a multiple digit number is considered as 3 separate integer values. For instance, when I have a space inserted to view the value of displayValue2 I'll get multiple values seperated with a space:

if (displayValue >= '0' && displayValue <= '9')
              {
           displayValue2 = displayValue - '0';
           Serial.print(" ");
           Serial.print(displayValue2); //  Display displayValue after conversion (debugging purposes)
              }

If I input 1234, I'll get:

1 2 3 4

To me, it seems how these are printed they are considered separate numbers?

I need to take each of these numbers and be able to define each as a digit on the 4 digit display.

Currently, if I input a single digit I can get the appropriate single digit to display. If I input a multi-digit number only the last number (1's place) is displayed where it should be.