Got it! So, we have 6324 and 1315, and we'll subtract the latter from the former.

Step 1: We'll start by subtracting the digit 5 and the borrow 0 from 4 in column 1 and get -1.
We add -1 to 10 and get 9 as the first digit of the result.

Step 2: We'll start by subtracting the digit 1 and the borrow 1 from 2 in column 2 and get 0.
0 is the next digit of our result.

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

Step 4: We'll start by subtracting the digit 1 and the borrow 0 from 6 in column 4 and get 5.
5 is the next digit of our result.

So, 6324 - 1315 = 5009.