Super,super Simple Poi

this is my 1st instructable, so pardon any unusual formatting.  I was looking at every poi instructable there was, but they were all very complicated, involving complex knots, or expensive materials. this one only uses 3 things: tennis balls, washers, and clothes-line.
I prefer the poi made with ropes as opposed to the ones made with nylons because the nylons wear out faster than the ropes do.       

So, you take the tennis ball, decide where you want the hole, and stab and widen the hole with a knife or scissors, as I did here.  If you are under 12, I would suggest you get an adult to help with this. Then you simply poke into the other side. repeat with other tennis ball   

the next step is to attach the rope. To do this, you tie an over-hand knot, and slip the washer over it, then pull the washer to the knot.

Now comes the tricky part. you have to push the rope up through both holes, starting with the big hole. 

The easy step! all you do in this one is: hold the tennis ball in your hand, pull the rope to your arm-pit, give it about 5 inches extra, and cut. then tie a knot at the end, wrap around your hand and type beginners guide to poi into the search bar! good luck!
because of a very good point made in a comment, i am posting a pic of the knot i use to tie them on to my hand. after copying the pic, then simply pull the knot fairly tight, slip on to your hand, and pull tight.