Once you have entered the expression, simply click on the Solve button. This will display all the steps of the solution process:

You can obtain an explanation for any step by clicking on it. Please note that you cannot click on the very first expression, which is the original problem. Quite often, several transformations will be performed within the same step. 

If you are not satisfied with the number of solution steps displayed (either too many steps or too few), click on the Options button to adjust the number of steps to be shown.