Keep a smooth stone in your pocket or purse whenever possible.
It should be a size that you can hold between your thumb and
forefinger comfortably, and somewhat flattened. When you find
yourself worrying about anything, get out your worry stone. Rub
it, and put all the tension and fretting into the stone. This is
particularly useful if it is a problem you can do nothing more about
at the present, but find you're spending lots of time thinking about.
Needless to say, it's a good idea to cleanse this stone frequently,
perhaps every New Moon. I actually have several worry stones I
keep on my dresser, so I can have a fresh one whenever I want it.