I'd really like to start making my own conditioner. While I have figured out that something in regular conditioners is making me break out, I can't seem to figure out what it actually is (for the most part, I've figured out fragrance free products work better for me). And I figure since I already make my own moisturizers, conditioner can't be that much harder.

Is there a beginners guide somewhere to making your own conditioner? As in, which chemicals work well for certain purposes?