"The first thing I've leardned from my life is that you mustn't worry about things that CAN happen. Of course you must be careful or have some plans, but if something bad happens and you worry that it will be so for a long time or just imagine the worst variant always - it never helps, just steals your forces for fighting with problems.
The second thing I learned from my life is that I haven't to try to use all my forces at once. I always tried to make every work in reserve to spare next day. So next day I was absolutely exhausted and couldn't enjoy this free time. So I decided I must do something only till the moment I want to explode this all :) And stop at once. And you know, it works!"