The comment I made about carrying such an item around in pocket or purse back in the post where how to make a center-pull ball was given has expanded to the point where it has focus here.
Choose your fibre. Wind it into a center-pull ball of a size to fit into pocket or purse or under a pillow or on the counter or by the phone or in a desk drawer…..
Next time you are cheerful or tearful or fearful, or bored or busy or sleepless, or distracted or contented or day-dreaming, or brain-storming or smiling or worried ………. take the pet yarn ball by its center-pull end and wrap it around your thumb again. And maybe again. You can do it fast or slow or in between. You can do it neat and tidy or not. You can wind at the base of the thumb or start under the thumb nail. You can watch it happen or do it without looking.