Sharyn,
Looking at your pics, you still have a couple or so good aerial roots. The browned roots should be trimmed off if they are soft or feel hollow. You can test it by just pressing on the brown roots. If soft and feels hollow, trim them off. Then repot in a clay pot, basket or net pot with coarse media which retains a little bit of moisture, but not much.
repotme.com has good recipes for orchid mixes. Although they don't note the ratio per ingredient, I adjust it according to the orchid. For example, if a vanda type, I would add more perlite or granite chips than coconut husk chips.
Orchid Mix Selected Blends
I tend to refer to the above web page when I want to try a mix. If I don't have a certain ingredient, I substitute it with something similar I have in my inventory, or go to a local nursery, OSH or Home Depot to find something similar.
