I have been told my entire life that a positive attitude can change everything here are some tips on staying positive.
1. Practice smiling: I enjoy doing this when I get caught at a red light. Look at the guy next to you and practice your creepiest smile. You'd be surprised how much someone else's uncomfortableness can make you feel better.
2. Use positive language: Say things like "I'm positive that today is going to suck", and "you are positively the most horrifying individual I have ever met" that last one is best said to a stranger and not your boss.
3. Share the joy: Tell others how much better you are doing than they are, this will help cement the feeling that you are doing great.
4. Never say yes again: Instead of saying yes to things say, "I'm positive!" this is a great way to let others know that you are positive. Would you like fries with that? I'm Positive!
5. Times of doubt: When you are in times of doubt and despair and are having trouble staying positive do little things to remind yourself that you can stay positive forever. Pick up a sick prostitute from the bad side of town wait two days then go to the doctor. You my friends can have a trained medical professional then tell you that you are positive!
Just remember folks it's all about the attitude.