This is a cheap and simple way to create a rainwater catchment system. It takes about an hour from start to finish, the only tool I used was a utility knife, and it costs under $15. Hopefully this project should be accessible to just about everyone. This is a good project for city dwellers with limited space or renters who aren't allowed on the roof, or don't have access to an outdoor hose...
•your favorite utility knife.
•a large container to act as the cistern. I used a rubbermaid tub gleaned from the street in front of our house.
•garden hose: the amount will depend on how far you'll need the water to travel for your gardening needs. Mine is 30'.
•a nozzle or valve for the watering end of the hose.
•gaskets or gasket material: some gaskets came with my hose, I used a bike inner tube for the rest.
•pvc threaded fittings: we're looking to trap the wall of the cistern tightly between gaskets at the point where the hose is attached.
•something to filter the rainwater and prevent evaporation. I used a coffee bag.
•a rope or bungie to tighten around your cover.
Step 1: about the fittings
You'll need two fittings: a threaded 'male' one for the inside of the tank, and a 'female' for attaching the hose to the outside. Again, we're sandwiching the tank wall between these two threaded fittings, and sealing it tight with gaskets on both the inside and outside. You'll need to make sure everything fits together before you leave the hardware store- mine had a rather limited selection, but if you have more choice, choose fittings that have more material supporting the sides of the cistern.