Cyano: knowing your hair properties means knowing if your hair is fine or coarse, high porosity or low porosity, dense or not, and if it has high or low elasticity.
You can try to sort that out by using this site:
Live Curly Live Free - Curly Hair Basics
And if after you tried to sort that out you still don't know your hair properties (like myself) then there is the posibility (but of course you don't have to) of ordering a hair analysis with the same website where they will analyse your hair for you.