Why don't you just focus on your mind?? Be mindful of your mind! The whole point of these practices is to become engrossed in the present moment. The mind takes you away from the present by thinking about past events and future possibilities. And it is virtually impossible to get the mind to stop thinking.
HOWEVER, it is possible to detach from those thoughts and not get swept up in the current. I find this to be an easier starting point than trying to shut off all thoughts completely. You will most certainly lose and become intensely frustrated and give up on a practice that holds so much potential for you!
You can do this by just listening to your mind, observe your mind while you walk. Instead of being the one that thinks about this thing or that thing, be the one that watches your mind thinking. In this way you will automatically become present. Say to yourself every so often, "What am I thinking about at this very moment?" Often times when I ask myself that, my mind goes blank. Even if just for a couple seconds . . . and it feels great. Then something happens . . . I trip on rock . . . or pass by a cute guy and my mind is off again!
Focusing on the breath gives the mind something to do. Heck, even repeating "lift, move, place" can become a mantra that gives your mind something to focus on.
But as you do these things just remember, YOU ARE NOT YOUR MIND! You are something different that USES your mind. Learning to stay present will help to keep your mind from using you. This will become more and more important as the human race evolves. If you can't control your mind, someone else will.
A great book for learning presence: The Power of NOW by Eckhart Tollehttp://www.amazon.com/Power-Now-Guide-Spiritual-Enlightenment/dp/1577311523