For a newbster, it’s tough to explain how to get an app icon to stay in the dock. The app runs, it appears in the dock. When you close the app, some icons stay and other disappear. Here is how to put an app in the dock and keep it there.
Three easy ways exist to get an app’s icon in the dock.
1. Open finder and drag and drop the app icon into the dock. It’ll stay and be happy there in the dock forever.
2. Find and run the app. When it appears in the dock, click and hold over the icon until the menu appears. Select Keep in Dock from this menu.
3. Find and run the app. When it appears on the dock, click and drag it to a new position on the dock. This action will lock the icon into the dock.