I recently cosplayed this exact same chi chi at animenext 2011
What I ended up doing for her outfit was buying a long plain blue dress and then I chopped off the straps and hemmed it. I used the left over fabric to make a mandarin- esque collar and loosely followed this tutorial here http://www.ehow.com/how_5251323_sew-...in-collar.html
I goofed up on the sewing though and made it a bit too small for my head so I added in a small zipper on the back. It was covered by my wig though so it all worked out. As for the detailing on the dress, I cut out long strips of pink/ reddish fabric and sewed on about 1 inch wide strips to the sides and arm holes of the dress to make the outline on the dress. Next I sewed on a 1/2 inch by 7 inch strip of fabric on to the front of the dress and added on 1/2 inch by 1 inch strips to give it that Chinese look.
For her armbands I drafted up a quick pattern by measuring the smallest part of my wrist and the thickest part of where it would extend to on my arms as well as how long I wanted the armbands to be. I sewed in some elastic before hand to make sure that it would fit over my hands yet also stay up on my arms and then sewed the armbands.
I didn't really bother getting too detail oriented for her shoes ( I just wore some black flats) but if you're picky you can always get some cheap flats or Chinese slippers and cover them with the same fabric that you used for her outline and armbands. I wouldn't recommend hot glueing the fabric on though, seeing as it might show through or get bumpy.
For her hair tie it's just a matter of using a left over piece of pink/ reddish fabric to cover an actual hair to hold her hair in place.
And Ta- da! You've got yourself a chi chi cosplay! I'll post some of my pictures soon to give you an idea of the final result. Good luck!