Stopping internal dialogue is tricky. It's like seeing, it's easy, but the barriers are so ingrained that it makes it hard to understand its simplicity. The easiest way I have found to stopping it is to visualize your thoughts, in words, floating across your mind. see them spelled out. This helps get over the hurdle of having a bunch of thoughts going on at the same time. It also helps to realize how mundane most internal chatter really is. Once your projecting them like that it makes it easier to move your real mind away from them. I think the hardest part is refraining from, at the moment, telling yourself your almost there, as this tends to throw one out of it, at least myself. And intend it my friend. Manifest quietude. Inner silence represents living in the now. Without the telling yourself your in the moment, just being in the moment. Walking works for some, but some peoples minds tend to go into chatter overload at this time. Breathing of course is very important as well, tuning into the natural rhythm of ourselves steers us away from pointless self banter. Deep abdominal breaths, slow and focused. Fast shallow breathing leads to more thoughts. Hope it helps, I still struggle with it myself, it's a tough one.