Now multiply the first number with the $1^{st}$ digit in $2^{nd}$ number to get intermediate results. That is Multiply 1239655 with 6. Write the result 7437930 at the end leaving 0 spaces to the right like this.
Now multiply the first number with the $2^{nd}$ digit in $2^{nd}$ number to get intermediate results. That is Multiply 1239655 with 5. Write the result 6198275 at the end leaving 1 spaces to the right like this.
Now multiply the first number with the $3^{rd}$ digit in $2^{nd}$ number to get intermediate results. That is Multiply 1239655 with 4. Write the result 4958620 at the end leaving 2 spaces to the right like this.