Hey B.V. you forgot #6. Have an ample supply of money to throw into the big
hole in the ground :-)

You need:

1. A big hole in the ground.
2. A liner for the big hole.
3. Water for the hole with the liner in it.
4. Fish to swim in the water in the liner in the hole.
5. A filtration system to clean the water holding the fish in the liner in
the hole.

To get to that point:

1. Buy some books. Any pond book with Helen Nash's name is a safe bet.
2. Search the web for backyard pond. The only thing better then reading a
Helen Nash book, is to read 100 web pages of people that have done this
before. Of course, you will get 100 different opinions.
3. Lurk here and read what others are doing, or pester everyone with 1000
questions posted here every day, which is what I did.

BV.