untreated wool works well but if you read she has an outfit already and wants to make it looked roughed up,treated wool doesnt work well with dye , i dont think you've dyed much material to say otherwise. wearing you outfit regularly will be the best way of making it look used.
I don't know why you say that wool doesn't dye that well. It takes a great number of colors in a veritable rainbow of shades. One needs to understand dye chemistry to a certain extent, but a basic dye bath of dyestuff, mordant and water + heat, can yield some results even for a beginner. Walnut hulls (the nuts are not necessary) should work for just about anyone, possibly too well. Just look around at a rendezvous, there's an entire population of guys wearing walnut dyed clothing! If you just want it to look messy and used, put on a pair of rubber gloves, pick up some black walnuts (this works well when they're still green and juicy), bruise them and rub them where you want the color. I don't recommend dyeing a finished garment made of wool. You're likely to end up with something a bit smaller than you'd like.
This page shows some samples of dyed wool (granted, it's Navajo, but some of the dyes are also used in European textiles from the period)
http://weavinginbeau...sandclassbegins
And in this video, a woman takes you through a sample book. She gets to walnut dyed yarn around 1:15 or so.
www.youtube.com/watch?v=q-dJuus0BlQ the video is called: Nancy Today: Natural dye 92) sample book of... (in case the link doesn't work).
Wearing your clothing as much as possible seems to be the best way to age things realistically. I have known people who hang their clothing out on the clothesline for weeks to let the weather get to it, but you'll need to hang it so it looks like it would when wearing it, not so you get the wear marks & sun bleaching half way down your breeches where they were folded over the line. Volunteer to muck stalls and do yard work in your period clothes. That'll do the trick, trust me! Nothing like horse sneezes to mess up a god jacket