How to set up an Outdoor Pond

The pleasure you'll get from your pond in the long run makes it worth the hassle of installing it.
Instructions
STEP 1: Lay out a bright-colored string on the ground in the outline of your proposed pond. If you're using a preformed pond, lay the liner out and outline it with string.
STEP 2: Look at it from your windows, patio and yard to be sure you like the location.
STEP 3: Use spray paint to mark the entire outline of your pond when you're satisfied with the shape and location.
STEP 4: Start about 3 inches out from the paint marks with a shovel and begin removing the sod and topsoil around the perimeter of the pond.
STEP 5: Lay a 2-by-4-inch board across the width of one end of the pond.
STEP 6: Set a carpenter's level on the board and make sure that the edge of the pond is level. Add topsoil to the edge if it's not.
STEP 7: Continue this process until you are certain that the entire pond edge is perfectly level. If it isn't, the liner will show where it's higher than the rest and could leak water where it's lower.
STEP 8: Start digging at the center of the pond. The walls should slope at about a 20 to 30 degree angle. Dig 2 inches deeper than the pond will be.
STEP 9: When the hole is complete, check for things poking out of the ground that might tear the liner, such as rocks or roots. Remove them if you find any.
STEP 10: Lay 2 inches of sand evenly across the bottom for drainage. It packs well if you get it wet.
STEP 11: Roll the liner out in the sun to heat it up. This will make it more flexible and easier to work with.
STEP 12: Lay the liner in the correct position in the pond, being careful not to move the sand too much.
STEP 13: Fill the pond with water.
STEP 14: Cut away the extra liner in places where it sticks up above ground level. Keep these pieces in case you need to patch the liner in the future.
STEP 15: Dechlorinate the water before you add fish and plants.
Tips & Warnings
Rooted plants typically are put into the pond in pots with a layer of gravel on top of the potting soil.

Rinse all of your plants before putting them in the pond. Soak them in a solution of 1 part bleach to 20 parts water. Dip the plant for about 2 minutes and rinse it immediately in cool running water. Next dip it in water treated with a dechlorinator to neutralize any remaining bleach.
The pond liner is by far the biggest expense, and the materials vary widely. Fish-grade PVC lasts between 7 and 15 years; fish-grade rubber will last twice that long. A preformed fiberglass pond will last about 50 years, while concrete could last as long as the house, though putting it in is a lot more work.