I'll try and help...
What you need to know can be cut down to the three main topic areas; Design, Properties and Performance (PAP) and The ATCFAI (Australian Textile, Clothing, Footwear and Allied Industries.)
As you probably already know the textiles exam is in three sections; The multiple choice, the short answers, and the extended response. The first two sections touch all three topic areas, while the final section has two questions; one on design, one on PAP, from which you answer one.
As someone suggested earlier, check out hsc.csu.edu.au but appart from that, if you have minimal notes etc, you can try searching the internet for the following.
Design
Make sure you understand all of the elements and principles of design. You know all the stuff about line, direction, shape etc. You are also required to know and understand a contempory, I think Australian, designer and their inspiration etc. (Common designers used in the HSC include Colette Dinnigan, Lisa Ho, and Morrisy)
PAP
For this section you should understand fabric finishes (eg scotch guard, fire retardent, water repellent etc) and fabric structures. you can be asked to draw a knit fabric etc. They will more than likely ask about different yarn structures as well as fibres and fibre blends.
ATCFAI
This is only a small part of the exam so don't stress too much. Try to find out about internal/external factors that can decide the success or failure of a designer (eg skill, economy, equipment.) There are also things about the protectionist policy, and other legilations to protect Australia imports and exports.
Well I hope i have helped...but...yeah, just seach some of this suff on the net and see how you go...Good Luck.
