Divide the numerator by the denominator
Use long division if needed
Add a decimal point and zeros to the numerator if the numerator is smaller than the denominator
Keep dividing until the remainder is zero or repeats
Write the quotient as the decimal
For mixed numbers, convert the fractional part the same way and add the whole number
For terminating decimals, stop when the division ends
For repeating decimals, mark the repeating digits if needed