While adding the shortcuts in the tool bar, click the shortcut and drag it to the toolbar and place it in the position you like it on the toolbar:
After adding the shortcuts, you can rearrange the toolbar by dragging and clicking the shortcuts, but make sure the Customize toolbar flyout is open. If the flyout is not open then the shortcuts' position will be locked:
If the toolbar size is small, the shortcuts will be present in the hamburger icon labeled "More". You can move shortcuts from here as well: