Next, enter the newly created directory and then launch PowerISO using the following command: It should look something like the following: Once the file is downloaded, you need to untar the file using the following command: Ensure that you have downloaded the file in your working directory. Remember, the free utility can only run under Mac command line window. Download the PowerISO for Mac Command Line Utility from the link. If you are not familiar with the command line, this approach is not recommended. Using PowerISO on Mac is a not simple process, it works under the command line without intuitive interface.