In the CD/Download versions of TurboTax, such as Home & Business, you can create more than one return with the software, whereas using the Online version only one return can be created. Thus, for the online version, the clear and start over option has to be used.
But for TurboTax Home & Business, you can simply start a New Return. On the top of the screen, select the File tab at the top left of the screen, then New Return. You will be asked if you want to save the current return you are working on and you can choose to say Yes or No, depending upon if you want to keep a copy. If you do decide to save a copy of the return you are not wanting, be sure to change the name of it to something that will alert you to it being an incorrect return.