521258 ÷ 2 
Our goal is to divide 521258 by 2.

Step 1:
If we divide 5 by 2, we get 2 and a remainder of 1.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
If we subtract 4 from 5, we get 1.
Fetch the next digit (2) from the dividend, attach it to 1 and continue: 12 / 2

Let's proceed to step 2:
12 divided by 2 is 6 with a remainder of 0.
Put 6 as the next digit of the answer. 
Result so far: 26.0
If we take 12 away from 12, we end up with 0.
Grab the next digit (1) from the dividend, add it to 0, then carry on: 1 / 2

On to step 3:
1 divided by 2 is 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 260.0
The remainder is 1 after subtracting 0 from 1.
Take the next digit (2) from the dividend and append it to 1, then repeat: 12 / 2

Going ahead to step 4:
The number 2 fits into 12 6 times, leaving a remainder of 0.
The number 6 becomes the next digit in our result. 
Result so far: 2606.0
If we take 12 away from 12, we end up with 0.
Take the next digit (5) from the dividend and append it to 0, then repeat: 5 / 2

Step 5:
If we divide 5 by 2, we get 2 and a remainder of 1.
Put 2 as the next digit of the answer. 
Result so far: 26062.0
If we subtract 4 from 5, we get 1.
Append the next digit (8) from the dividend to 1 and continue with: 18 / 2

Let's proceed to step 6:
The number 2 fits into 18 9 times, leaving a remainder of 0.
Write down 9 as next digit of the result. 
Result so far: 260629.0
If we subtract 18 from 18, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 7:
The number 2 fits into 0 0 times, leaving a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 260629.0
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 8:
When dividing 0 by 2, we get 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 260629.0
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 260629.0, with a leftover of 0.0.