To convert a decimal into a fraction, follow these steps:

- Identify the place value of the decimal number. For example, if the decimal is 0.25, the 2 is in the tenths place and the 5 is in the hundredths place.

- Write the decimal number as the numerator of the fraction.
- For the denominator, write 1 followed by the same number of zeros as the number of decimal places. For example, for 0.25, write 25 as the numerator and 100 as the denominator.

- Simplify the fraction by finding the greatest common divisor (GCD) of the numerator and denominator and dividing both by it.
- In the example of 0.25, the GCD of 25 and 100 is 25. Dividing both by 25 gives the simplified fraction 1/4.

- The final answer after converting the decimal 0.25 into a fraction is 1/4.