Watering your garden should preferably be done with rain water. However, sometimes using tap water is unavoidable. In such a case one should, as with all natural resources, be efficient and sensible.
Ever noticed how a small pinch hole in your garden hose is capable of wetting a large area?

Many commercial sprinklers have 2 things in common: they are expensive and not very efficient. They seem to be designed with the idea of getting a lot of water in the air hoping it will land somewhere where water is required.

This device relies more on pressure than on size, creating a fine sheet of water. This I'ble will show you how to build this very cheap and simple lawn sprinkler and it will show you how to customize you sprinkler by going into some patterns.

If you like my idea, don't forget to vote for me in the "Garden Contest".

Step 1: How to Make It.

It's quite simple: a pipe and two legs. Due to the round legs, it slides quite easily over your lawn when you pull the hose (so you don't get wet).

What you need.
An Aluminium tube (OD 10 mm)
2 PVC pipes
Hose clamp

How it is made.
Drill a 10 mm hole trough both PVC pipes.
Insert the Aluminium pipe through the PVC pipes.
Saw a notch (more about patterns in the next step).
Plug the end of the pipe.
Connect hose and clamp.

You can rotate the tube in its legs to aim the water curtain at a specific region. Be careful not to point it downward too much or you end up soaking the earth beneath it.

You can make this fairly long (or short) to meet your requirements. Be aware that over a distance you gradually loose pressure. Secondly, very long ones can become weak (you should add an extra PVC "leg" in the middle).

Step 2: Patterns.

This step is about patterns. Depending on your requirements and water pressure, you can use your own design. Below I suggest 3 cutting patterns.
Make sure you have a sharp iron saw. When I first used a fairly blunt one, the roughness of the cut caused strange unwanted patterns.

In the picture you see three different notches I have tried:

Vertical notches
will generate a sheet that has the shape of a pizza slice.

Angled notches
will point the sheet in a certain direction. Ideal for dead corners like flower beds.

Cross cut notches
will combine a bit of both.

Best is not to cut the notches very deep (you want a high pressure and low water consumption) because you can always cut deeper if it doesn't work at once. In this way you can gradually determine the depth of your notch.
I was surprised by the effect of one small notch. The notches in the first picture are definitely too deep.

Spacing. I have started with one cross notch because the area is not large. I figured if it didn't work, I could always cut some more.

If you think you have an alternative patterns that works, you can always test it on a small piece of copper tubing before you decide to make the final cut.