How to make crochet - Stress balls

Stress balls are simple and aren't too time consuming (the one in the instructions took me 1-2 hours to make), I used to fill these with rubble and use them for juggling or playing catch. Lately I decided to try making them again and found an old pillow that makes for good filling.
Here are general instructions about making them:

First you chain 5 and connect with the first chain. Then you go around once with single crochet twice in every hole. Then every second is 2 in one hole, every third and so on.

When you get to every 6-7 you''ll have about a fist sized ball if you start with the next part.
After deciding on your size go around 3 rounds with only single crochet in every chain. adding chains increases the width, skipping chains decreases it while doing normal single crochets makes a cylinder or the width remains constant.

Next you start skipping chains starting with the number you ended adding +1, so if I was adding every 7th I'll start removing every 8th, then every seventh and so on. when you get to around skipping every second you can start filling it while the gap isn't too small.

After filling with and getting to skipping every chain continue skipping until the gap is gone. Tie the end by pulling the string through your final chain and tightening. Push your crochet needle through the bottom and pull the excess string. Do this once or twice from bottom to top, top to bottom, this is also where you adjust the round shape of the result. you can just pull the remainder completely inside the ball and it won't untie.

Here's a hacky sack filled with rice made from t-shirt yarn thank's to @cryptocariad and their post/tutorial
Also thanks to @crystalize for the filling idea :D


Hope your try was a success and you have a cool new stress ball to play around with :)
If you have any questions feel free to ask.