Okay I'm kind of a noob but I'll try to hep you out
I'm looking through some costumes here and online of her, and the ones that look the best most often have:
1. Darker tan for the body of the dress, not yellow.
2. The Fabric looks 'furry' like a faux suede or something. I'd avoid crushed velvet and stuff like that that's really shiny on camera. It's supposed to be made out of an animal hide or some sort, going by historical context.
3. The Fringe is always thin. You can actually use tassel-like material here or you can rip thin shreds of cotton or some material, leaving a at least a 1/4 inch border on the end for easy sewing.
4. Make the necklace out of sculpey or another easy bake clay. It comes in all colors or you can paint it.
5. There's a number of method for using like duct tape and stuff to make ghetto home made patterns in the sewing and patterns tutorial forum.
6. I recommend Liquid Latex or (it that's too pricey) face painting crayons like you would get cheaply in party city makeup stores. Set it with powder though so it doesn't smudge.
Good luck just ask if you want more suggestions!
And I hope this helps you out at least a little