We have numbers 1581 and 3044. Let's start adding them together.

Step 1: We'll start by adding the digits 1 & 4 in column 1 and get 5.

Step 2: We'll start by adding the digits 8 & 4 in column 2 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 5 & 0 in column 3 and get 6.

Step 4: We'll start by adding the digits 1 & 3 in column 4 and get 4.

So, 1581 + 3044 = 4625.

