My (and maybe others?) difficulty with MVVM was to understand a simple thing: View knows about ViewModel. I was using bindings and commands, but they are simple strings in xaml. Because of safe resolving at run-time (safe means you can do a typo, but software will not crash) this makes view decoupled from view-model (at compile time at least). And I was always looking for solution to keep this decoupling, to example, behaviors.
Truth is, you can get access directly to view model, which is typically a DataContext of window/user control:
var vm = (MyViewModel)this.DataContext;
Knowing that, using events probably the best way to call view method from view model, because view model don’t know if there is subscriber, it just firing that event and event can be used by view or another view model.
// define in the view model
public delegate void MyEventAction(string someParameter, ...);
public event MyEventAction MyEvent;
// rise event when you need to
MyEvent?.Invoke("123", ...);
// in the view
var vm = (MyViewModel)DataContext;
vm.MyEvent += (someParameter, ...) => ... // do something