It seems simple, but the reality is that many serious falls take place in places that should not be that technical. Many falls take place in spots that could easily be negotiated with good technique.
When I started working at the Institute, I had quite a bit of experience. I intrinsically understood the techniques for walking on snow and on ice, but they weren't well defined in my head. Well defined techniques lead to better techniques.
The primary snow/ice-walking technique that I'm referring to is the in-balance vs. out-of-balance step. These steps are designed to be used on 30 degree to 50 degree terrain. And if they are used properly, a climber will be able to ascend a slope with a great deal of security.
In-balance and out-of-balance (the cross-over step) walking provides you with stability and a strong sense of when you are safe and when you are not. With practice it allows climbers to move effectively and safely over steepish terrain.
When one is in-balance, both feet are situated in such a way that if you stop, you will be completely stable. I shot the above photo looking down at my feet while I was in-balance. If you are carrying an ice-axe, it is best to move the axe from one placement into the next while you are still in-balance. The axe should never move while you are out-of-balance. If it stays stationary while out-of-balance, it will provide an extra point of security during less secure movements.
The above picture shows a climber taking an out-of-balance step in snow. Note that his left foot is directly above his right foot.
Clearly in the snow that the above climber is moving in, such a step is not required. One need only to move in-balance and out-of-balance in terrain that requires additional security...like on steep ice...
The in-balance out-of-balance step is incredibly useful while wearing crampons. The cross-over step allows the ankles to bend in such a way that all of the crampon points on the bottom of the boot are engaged in the ice. You'll note in the above picture, that the climber's toe is nearly pointing down hill. This allows every point to engage.
The movements required for good in-balance and out-of-balance walking are not hard to master. And the reality is that most of the time that you are moving in the mountains, such steps are not required at all. It is only when the terrain becomes steep or dangerous that it really becomes important. Indeed, the important part is not just moving properly but being aware of your movement. In other words, always knowing when you are in-balance or out-of-balance leads to more security in the mountains.