Hey darlin,
Happy to share.

Two factors make up a great skirt--the right ratio in the tiers, and the FABRIC!

If your fabric is too stiff or too light, it won't "fly". Of course, too heavy can mean it will have a tendency to slide right off of your hips, too. *grin*

I use a medium weight quilting cotton, 100% cotton. Poly blends tend to be stiffer, in my experience, and never soften with washing to rectify it. The specific brand I use is "Springs" and the line is called "Natural Charm". I personally avoid the Kona Cotton lines commonly available at the craft stores because it is too thick and stiff for this project.

Even better than cotton is a medium weight rayon. Again, be careful not to get one that is too heavy, or it will be a burden to wear. With spring and summer on the horizon, you have better luck of finding this fabric in the stores right now!

The ratio is a simple 2:1. I use the width of the cotton, which is 42" (closer to 41" when washed--I pre-wash my fabrics).

Top tier is 2 panels
Middle is 4
Bottom is 8

So with the seams taken into account, the top tier is around 80", middle is around 160". and bottom is 320". Voila. Just shy of 10 yards. If you want to be picky about it and add an additional panel to push it over the top, you can do it. But for me, I have a gathering foot on my machine which does all the work for me, and calibrating it to a 2:1 ratio for the fabric I am using is far easier than trying to ease in an odd number of panels by hand.

For trims, you can use something as simple as satin blanket binding. I did all my trims myself--cut it into 8" wide strips, which I would fold, iron, and then attach to the skirts (this is what Flying Skirts does as well). It gave me a better variety of trim fabrics to choose from. However, be careful on this choice as well--you need to find a balance between a fabric that is light enough to flow with the skirt and won't be a stiff edge, but also sturdy enough to survive being dragged and stepped on. Anything too delicate will fray and you will have to replace the trim before too many wearings. The blanket binding, while stiffer than I prefer, is a good choice because it is all ready to be sewn on, and wears well. And is cheap and easy to replace if I wear it out.

I hope that answered your questions. If not, ask away!

And for the record, you can definitely save a dime by making your own skirt, but for a long-lasting skirt you will THANK yourself for buying when you try it on and twirl in it, buy from Flying Skirts. There is a reason they are the de-facto 10-yard skirt manufacturer for tribal bellydancers. The skirts are stellar. I recommend the spinning skirt with trim. Avoid the tempting cheaper skirts made from gauze--they are too light for really good skirtwork. They really are only good for practice where no skirtwork is the focus. And don't skip the trim--you will see everyone else's colorful bands of color and just want it in the long run. trust me. :)