I learned a lot reading the live curly live free site. Here is what I learned there and here.
Porosity is easy to figure out. Run your fingers up a strand of hair from tip to root. If your hair feels smooth, you have low porosity. If it feels rough you have high porosity. If it's kinda bumpy but not rough, you are medium. Porous hair tends to like protein, non porous hair tends to prefer oils.
Fine hair tends to prefer protein, coarse hair tends to prefer oils.
Another test is hair elasticity. Take a shed hair and pull it. If it beaks without stretching much, it has enough protein and needs more moisturizing (oils, mostly). If the hair stretches and doesn't bounce back, it needs more protein. Healthy balanced hair will stretch 20-50% and contact back to its original length pretty quickly.
Also, hair with too much protein will tend to feel dry, stiff, and straw like. Over-moisturized hair will tend to feel very soft, fly away, and prone to frizz.
If your hair has conflicting properties or your hair is a mix of textures, I'm afraid you'll just have to do some experimenting with products to find the right balance.
2c/3a-M-ii porous, good elasticity, APL, dark brown with a silver lining. Biggest enemy: frizz!
Last edited by earthnut; 07-02-2012 at 04:51 PM.