Publishers

Step 1: Define variables. Keep them as simple names such as "apples" and "price". Add as many variables as needed. Avoid using extraneous symbols such as parenthesis "(" or slashes "/". Avoid spaces inside variables. Simple words will lead to the least amount of errors.
Variable

Step 2: Define your calculation. For example, "TotalPrice = apples * price" (without quotation marks). Define as many calculations as needed.
Calculation

Step 3: Define the results displayed by the calculator. For example, "TotalPrice".
Output

Step 4: Add the Calculate Button for the user.

Step 5: Add the Output Area for the Calculator. This is where the page will display results from the calculation.

Step 6: Review the Javascript code, this is optional. Make sure the variables in the equation match the previously defined variables. If you make changes, make sure they will follow the rules of Javascript.
Code

Step 7: Review the HTML code, this is optional. If you make changes, make sure HTML rules are followed. Click on Preview to see how the page will look.
HTML

Step 8: Press on Create Calculator to combine the Javascript and HTML to make a fully functional page.
Create Calculator

Step 9: Press on Preview to get the final fully functional page.

Step 10: Save the page for publication. If you would like to host the page on this website with your own Adsense code, let me know. Adsense is Google's advertising program which lets publishers earn money.