A positive attitude is both good for your health and a crucial ingredient for success in life.  Somedays it is difficult to maintain and some never had one to start.  One easy step to get you going is this...  Divide a sheet of paper into two columns.  For a few days, jot down, in the left column, all of the negative thoughts that come into your head.  Rewrite each thought in a positive way in the right column. For example, "I will never get this finished by the end of the day!" could become, "I will probably get most of this finished by the end of the day."  If you practice this enough, it will start to come naturally.

And keep this little quote in mind by a wise man named Herm Albright.  "A positive attitude may not solve all of your problems, but it will annoy enough people to make it worth the effort."