First, a tip.
“Hot potato” is a game where everyone quickly tosses a ball around, and when the music stops the person holding the ball is eliminated. It suggests an analogy for a way to practice seeing. Every point you look at is a hot potato. The longer you stay on it, the more likely you will get burned. And the larger the point, the more likely you will get burned (big potatoes make for big burns, right?). So your best bet is to keep moving among the tiniest points as quickly as you can, never stopping long enough for your eyes to suffer abuse from getting burned by the potato. Anyway, it was just a thought, and you might try thinking of it in this way to see if it makes shifting easier.
Now some clarification on the principle of movement for vision improvement. It’s an idea that’s given a lot of importance by many writers about the Bates method. It’s got to be put in the right context or it doesn’t make any sense.
When you look for small details within that which you’re looking at and don’t feel like you’re moving your eyes, it isn’t a bad thing. You shouldn’t feel your eye movements or try to force eye movements with the idea that you’re preventing staring. In doing that you shift your eyes without shifting your attention and the important thing is really your attention. You can’t look at something right if you don’t pay attention to it. Consider the common sense test: Do people with normal vision move their eyes just for the sake of moving them, because that’s the right thing to do? Of course not. They move their eyes only because that’s what happens when they direct their attention to another object or a different detail.
Now on the pattern of movement. If you watch a person with normal vision, his eyes don’t always dart around much to far apart objects. Much of the time his eyes appear to not be moving at all, because his shifts are so short as to be imperceptible. His process of looking at things is a matter of continuously looking for details and looking within those details to find further smaller details of interest.
If he is not searching a wide area or looking around, he looks at the details of one thing at a time. And even when he is looking over a wider area, he still keeps stopping for an instant on points, ie: it’s not a smooth movement. Don’t be trying to learn a way to move your eyes to make the movement as smooth as possible. The eyes are made to move instantaneously to point themselves from one detail to the next. If you’re making a slow, smooth movement, you aren’t paying attention to what you’re looking at. Make your attention your starting point. Make the decision of paying attention to tiny points in quick succession. Your eyes will follow.