Turn on the calculator
Enter the number you want the square root of
Press the square root button, usually labeled √
Read the result on the display
If there is no square root button, use the exponent button and enter 0.5
For example, calculate 25^0.5 to get 5
On some calculators, press the function key first, then the number, then the square root key
Check the result if needed by multiplying it by itself