The reason they are known as devil sticks is that when you get good at tricks, it looks like the sticks are moving by magic, and therefore "the work of the devil." It's all about illusion.
Juggling Sticks are a lot of fun to make and play with, and suitable for kids (every make is a great opportunity to teach children how to use tools safely as well as developing confidence and skills, spending quality time together and encouraging curiosity, independence and knowledge about how things work).
Cost: under $4 per set. (That's New Zealand dollars, works out at around 2.50 Euro, 2 Pounds or $3.25 US)
You can see another way of making these, with different materials here thanks to origamiwolf.
A couple of videos (not mine): simple tricks anyone can pick up in half an hour / fancy pants performance sticks (skip to 1.39 for interesting stuff; don't play with fire without proper training/supervision, and don't play on train tracks. /endpublicserviceannouncement).
Step 1: What You'll Need
Grip - Recycled inner tubes from bicycles - in New Zealand, you can go to any cycle shop and ask them for old inner tubes they no longer want, they're usually happy to get rid of it.. 3 long thin strips about 10mm wide and at least 1m length, and 2 short wide pieces about 210 x 100mm.
Insulation or electrical tape (colours are purely for aesthetics - the rasta yellow/red/green is popular)
Staple gun and staples (or tacks)
Step 2: Attach the Grip
Do not attach it too close to the edge of the rubber piece, as you will be pulling it tightly and you don't want it to pull out from under the staple.
Use the hammer as necessary to ensure the staple is secure.
Step 3: Wrapping the Grip
When you reach the end of the stick, wrap the rubber around the end once, then change direction again and travel back up the stick, the new stripes will make a criss-cross pattern. In the last photo, you can see yellow between the rubber - this is duraseal (cover seal) - I cut a strip about 4cm wide and stuck it to the stick before wrapping the grip around it. The hand sticks of the yellow set are wrapped differently - just leaving no gaps and overlapping the inner tube as you wrap it. This uses more tubing, and is purely for aesthetics - it makes no difference to the performance of the sticks.
When you reach the top again, give it a final wrap around and staple securely.
Cut the excess tubing off, but not too close to the staple (when the tension is released, the rubber might slip through the staple if it is cut too close).
Step 4: Finishing the Handsticks
Do the same to the other end if you wish. Use as many colours as you like - I've just used a single red strip here. In other photos you can see I've used blue, and a combination of yellow-white-yellow.
Repeat steps 2 and 3 for the second handstick, and apply tape to match (or not, your choice).
Step 5: Wrapping the Throwing Stick
Prepare the tassels by cutting strips half way into the larger pieces of rubber as shown in the photo. The more strips there are, and the thicker the rubber used for this part, the more air resistance will be produced and the slower the stick will spin (use thick rubber and cut thin strips for beginners, lighter-weight rubber and thicker strips for a faster spin. The pros tend to use sticks with no tassels, and often a throwing stick that is tapered to a narrow point in the middle with thicker ends, which spin really fast).
Attach the solid part of the rubber to the stick with two staples, again not too close to the edge of the rubber.
Wrap it tightly around the stick. If children are making the sticks, this is the part where adults may need to step in, as children may not have the strength in their hands and fingers to pull it tight enough. If it is loose, it will slip off the end of the stick while you play.
Staple closed and wrap with tape, then do the same at the other end.
Step 6: Find the Balance Point (optional)
Balance the throwing stick on one finger to find the balance point (should be near the centre of the stick). If you like, you can mark this point with a piece of tape. This helps as a visual reference when playing and learning tricks.
You can also put a small rubber band (or a cross section of a small tire) around each end of the throwing stick. That way, when you're not playing, you can keep all three sticks securely together in one place.
This is my first instructable, so let me know how I can improve it, and feel free to ask any questions.