I eyeball everything so practical measurements would be determined by the size container you have and how much you want to make.

Think 80/20 with compost to coco coir, perlite is to help with drainage and worm castings is a great organic boost of nutrients. Roots like to be moist, not wet, and in a fluffy well draining soil mixture 😉

This can be repeated when planting seedlings directly in ground or in your containers. Try it out, I hope it works as well for you as it does for me!