These are the excerpts from one of my favorite book by Dale Carnegie
RULE 1: If you want to avoid worry, do what Sir William Osier did: Live in “day-tight compartments”. Don’t stew about the future. Just live each day until bedtime.
RULE 2: The next time Trouble-with a capital T- comes gunning for you and backs you up in a corner, try the magic formula of Willis H. Carrier:
a. Ask yourself, “What is the worst that can possibly happen if I can’t solve my problem?”
b. Prepare yourself mentally to accept the worst-if necessary.
c. Then calmly try to improve upon the worst-which you have already mentally • agreed to accept.
RULE 3: Remind yourself of the exorbitant price you can pay for worry in terms of your health. “Business men who do not know how to fight worry die young.”