Free pattern and free video tutorial! You can see the video here on my website:
https://verypink.com/2018/03/21/orb-knit-ball/

Get creative and use this simple ball pattern in endless ways! Experiment with different yarns, colors, stripes, and stuffings to make baby toys, dog toys, Christmas ornaments, juggling balls, hacky-sacks, etc.

You can use any weight of yarn and any double-pointed needle size, as long as you like the size and fabric it creates. Examples of the different sizes are in the free video tutorial.