How to install a DMG file on Mac: MacWashing as an example

Download the DMG file

1. Open the MacWashing download page and click Download for Mac. The browser saves a file named like MacWashing-2.3.6.dmg to your Downloads folder.
2. Open Downloads: click it in the Finder sidebar or choose Go › Downloads in Finder.

How to install a DMG file on Mac

1. Double-click the .dmg file. macOS checks it for a few seconds and opens a window with the app and the Applications folder.

2. Drag the MacWashing icon onto the Applications folder in that window. macOS copies the app.
3. Eject the disk image: click the eject button next to MacWashing in the Finder sidebar, or Control-click its icon on the desktop and choose Eject.
4. The .dmg file is no longer needed. You can move it from Downloads to the Trash.

Don’t run the app straight from the disk image window: after you eject the image, the app is gone. Always copy it to Applications first.

Open the app for the first time

1. Open the Applications folder (Go › Applications in Finder) and double-click MacWashing.

2. macOS asks whether you want to open an app downloaded from the internet. Click Open. macOS asks this only once: Apple has checked the app, and the question is there so that nothing opens without your say.

How to give full disk access on Mac

Many apps that work with files ask for Full Disk Access: without it, macOS hides caches, mail and other apps’ data from them. MacWashing asks for it on its first screen, together with a helper for system folders.

1. Next to Full Disk Access, click Open Settings.

2. System Settings opens Privacy & Security › Full Disk Access. Turn on the switch next to MacWashing and confirm with your password or Touch ID. If MacWashing isn’t in the list, click + below it, or drag the app icon from the tip MacWashing shows next to the window.

3. If macOS offers to quit and reopen the app, you can click Later: MacWashing sees the access anyway.
4. Back in MacWashing, next to System Folders Helper, click Install. macOS opens General › Login Items & Extensions. Turn on the switch the tip next to the window points to and confirm with your password or Touch ID. On macOS 26, background items are listed by developer, so the switch carries the developer’s name rather than the app’s.
5. When both steps are checked, click Get Started. You can also click Later and give the permissions in MacWashing’s Settings › General › Access at any time.

Free mode, a license and signing in

MacWashing works right after installing, without an account. Every section is open: System Junk and the Uninstaller free up to 25 GB in total for free, and Large Files, Storage and Privacy have no limit. Scheduled auto-clean needs a license.

1. To use a license, click Sign In at the bottom of the sidebar.

2. The browser opens the sign-in page. Sign in to your account or sign up, then confirm. MacWashing continues by itself and activates the license on this Mac.