The four steps used to Calculate Square Roots are: 1  A-Guess-Estimate the square root of the radicand. ( 2 The initial estimate can be any number. 3  Subsequent steps will refine the estimate.). 4  B-Multiply the estimate by itself. 5  C-Check-Compare the product obtained in step B (above) with the radicand. 6  D-Refine the Estimate.