What we do is to allow ourselves to be aware of our thoughts and we will then find that they subside and dissolve of their own accord. An example is meditating on our breath. We are allowing our thoughts to intervene. The practice is returning to the breath, not staying with no thought.
In my experience we can *never* make ourselves think or not think anything. There is a famous experiment where we can try not to think of Pink Elephants. You can try it if you want now. The harder you try, the more invasive the thoughts of Pink Elephants become.
Trying to force ourselves to think, or to not think, in a particular way can be a destructive process.
Observing our thoughts, listening to them in effect, silences them because the source of our awareness becomes the silent watcher of our thoughts and not the thoughts themselves.
When that happens, when focus on our inner dialogue is no longer the source of our awareness, we can say that we are mindful for that time.