I like your in the moment "Here... now" mantra, greatdane. I'll try that.
I sometimes use a mantra like "Om mani padme hum," but I feel like I'm not as able to clear my mind when I do. I still use mantras as a calming thing though. I got one in a dream, it's just a nonsense fragment really, but it calms me.
For meditation, just focusing on my breath works better for me. At first I counted my breaths, because it was recommended in a book on meditation, but I found it made me competitive with myself!
So I tried counting just to ten, then starting over. Better, but it was still too much of a game. Now I just count to one. Over and over. Breathe in, "One," breathe out. That's what works best for me.
I'm still pretty rubbish at meditation, and I have monkey mind all too often, but it helps me anyway. If I keep at it maybe someday I'll learn to levitate.