There are lots of tricks that you can do to make a Old Republic Jedi costume look good, that I did not know when I made mine.
First, get good fabrics. Do not make the final garment out of muslin.
Adjust the pattern so that it will fit the body of the person who will carry it, so that it will not look baggy.
The tunics are not simple triangles in the front, like a Karate gi. The neck hem of the inner tunic ends over the chest and then the edge goes straight down. (See Anakin's tunic in AOTC on the balcony on Naboo)
The outer tunics are made from separate pieces from the waist down, that flare out like skirts - this allows you to fit the waist to the person carrying the costume and it allows for more mobility.
The tabards are often made from separate pieces from the waist down so that the tabards point down below the waist and do not cross. Over the chest, Obi-Wan's and Mace Windu's tabards are even slightly curved.
The shoulder seams are not curved - they are tucked in and fastened!
One common problem when costuming as a Jedi is called "gapitis", where the tunic opens up too much. To prevent this, you can use a trick from Karate gi's - add straps at the waists that you tie together. Then, the tunic will hold together without the belt.
Here are some resources for a beginner (at this costume):
http://boards.theforce.net/costuming_and_props/b10019/10839596/p1
http://www.padawansguide.com/basic.shtml
There are web site/forums devoted to costuming as Anakin and Obi-Wan, that could contain much info that could be applicable to other Jedi costumes as well:
http://www.crazyoldwizards.com.ar/forum/default.asp
http://www.sonsofthesuns.com/
PM me your email address if you want me to send you my high-res pics of Mace Windu's costume.
I guess I need a bead on good patterns. I've seen the commercially available costume Jedi patterns. Are they any good? He's interested in the Mace Windu robe style, though he's not set on it.
