Alright, let's solve this problem step by step. We have 868680 and 10249, and we're subtracting the second number from the first.

Step 1: We'll start by subtracting the digit 9 and the borrow 0 from 0 in column 1 and get -9.
We add -9 to 10 and get 1 as the first digit of the result.

Step 2: We'll start by subtracting the digit 4 and the borrow 1 from 8 in column 2 and get 3.
3 is the next digit of our result.

Step 3: We'll start by subtracting the digit 2 and the borrow 0 from 6 in column 3 and get 4.
4 is the next digit of our result.

Step 4: We'll start by subtracting the digit 0 and the borrow 0 from 8 in column 4 and get 8.
8 is the next digit of our result.

Step 5: We'll start by subtracting the digit 1 and the borrow 0 from 6 in column 5 and get 5.
5 is the next digit of our result.

Step 6: We'll start by subtracting the digit 0 and the borrow 0 from 8 in column 6 and get 8.
8 is the next digit of our result.

So, 868680 - 10249 = 858431.