Once you’ve downloaded HandBrake for Mac, open the disk image in your Downloads folder. Your web browser (e.g. Safari, Firefox, or Chrome) may do this for you automatically. Then drag the HandBrake application to your Applications folder.
HandBrake is now installed. You may eject the disk image and move it to the Trash.
You may launch HandBrake by quickly clicking twice (double-clicking) on the cocktail & pineapple icon. Depending on your system settings, a single click may suffice.